Defense, Aggression, and Pogos as Prey
Wrestling and stinging
ants, lunch for spiders, and territorial wars. Pogonomyrmex spp.
ants at various locations in North America.
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![<span class="captionImageInfo"> ● Horse Ridge, SE of Bend [Deschutes Co], OR USA [el. 1310 m / 4297 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.00047a3daca81cf459487&ll=43.912533,-121.007083&spn=0.086565,0.145912&z=12&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 7/20/09 7:14AM sunny, air temp: 11°C / 52°F </span>
<div class="captionImageMain">Unlike many other <a href="http://www.davidlouisquinn.com/pogolumina_PogonomyrmexInfo.htm"><span class="glossLinkSm">Pogo</span></a> species, a majority of the <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>P. salinus</em> </span></a> ants we encounter are very docile, and tolerate our presence with no signs of defensive behavior (usually ignoring us completely). Occasionally, however, we come across a colony populated by extremely pugnacious workers. On our first visit to this gigantic nest (July 2008) I was unable to approach the entrance, due to the many angry defenders. On the second visit (one year later - when this image was captured), we arrived when the temperature was still too low for the ants to be active, and waited for the first to emerge...
This worker was one of the first to come out. She stood in the sun just outside the entrance, and attempted to menace us with a feeble opening and closing of the <a href="http://www.davidlouisquinn.com/pogolumina_mandiblesInfo.htm"><span class="glossLinkSm">mandibles</span></a> (note the worn, blunt 'teeth'). At 11°C / 52°F, the air temperature was still too low for vigorous activity, though the rocky surface where this ant stood had already reached a surface temperature of approx. 20°C / 69°F. Facing east, this nest is constructed around large rocks which act as solar collectors - allowing its inhabitants to become active well before those of any other nest in the immediate vicinity that we have observed. Within an hour, many workers were active and becoming agitated, so I retreated. <span class ="footnoteTag">[scroll down for additional notes/references]</span>
</div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>On our first visit to this nest (7/15/08) the air temperature was 28°C / 82°F, and the ants were foraging along a trail in the shade of a large rock. Soon after I approached the entrance, many dozens of workers (defenders) poured out, and ran toward me. Most turned back after I backed away, but approximately 10 workers continued pursuing me more than 3.6 m / 12 ft from the entrance, often stopping to stand on small pebbles and twigs while waving their antennae wildly, and opening their mandibles.
At many other P. salinus nests nearby, workers were not aggressive, and ignored us - even when inches away from the entrances.
We think the physical size of the large nest (mentioned above), may have something to do with the very aggressive worker response to our presence. The gravel-covering of this nest was approx. 1.9 m / 76 in. wide, measured on its longest axis. This means that I had to walk over a large portion of the nest 'dome' in order to reach the entrance - undoubtedly collapsing many tunnels and galleries that lay just below the gravel covered surface. This would result in alarm pheromones being released in great quantities by the ants underfoot, alerting nestmates to the defense of their colony.</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-vT4mdwg/9/54624c60/L/0499_09_40f-L.jpg)
● Horse Ridge, SE of Bend [Deschutes Co], OR USA [el. 1310 m / 4297 ft] view location in Google Maps » ● 7/20/09 7:14AM sunny, air temp: 11°C / 52°F
Unlike many other Pogo species, a majority of the P. salinus ants we encounter are very docile, and tolerate our presence with no signs of defensive behavior (usually ignoring us completely). Occasionally, however, we come across a colony populated by extremely pugnacious workers. On our first visit to this gigantic nest (July 2008) I was unable to approach the entrance, due to the many angry defenders. On the second visit (one year later - when this image was captured), we arrived when the temperature was still too low for the ants to be active, and waited for the first to emerge...
This worker was one of the first to come out. She stood in the sun just outside the entrance, and attempted to menace us with a feeble opening and closing of the mandibles (note the worn, blunt 'teeth'). At 11°C / 52°F, the air temperature was still too low for vigorous activity, though the rocky surface where this ant stood had already reached a surface temperature of approx. 20°C / 69°F. Facing east, this nest is constructed around large rocks which act as solar collectors - allowing its inhabitants to become active well before those of any other nest in the immediate vicinity that we have observed. Within an hour, many workers were active and becoming agitated, so I retreated. [scroll down for additional notes/references]
ADDITIONAL NOTES/REFERENCES:
On our first visit to this nest (7/15/08) the air temperature was 28°C / 82°F, and the ants were foraging along a trail in the shade of a large rock. Soon after I approached the entrance, many dozens of workers (defenders) poured out, and ran toward me. Most turned back after I backed away, but approximately 10 workers continued pursuing me more than 3.6 m / 12 ft from the entrance, often stopping to stand on small pebbles and twigs while waving their antennae wildly, and opening their mandibles.
At many other P. salinus nests nearby, workers were not aggressive, and ignored us - even when inches away from the entrances.
We think the physical size of the large nest (mentioned above), may have something to do with the very aggressive worker response to our presence. The gravel-covering of this nest was approx. 1.9 m / 76 in. wide, measured on its longest axis. This means that I had to walk over a large portion of the nest 'dome' in order to reach the entrance - undoubtedly collapsing many tunnels and galleries that lay just below the gravel covered surface. This would result in alarm pheromones being released in great quantities by the ants underfoot, alerting nestmates to the defense of their colony.
pogopogonomyrmexpogonomyrmex salinusantspreydefensemacroharvester ants
![<span class="captionImageInfo"> ● Duval Mine Rd, Sahuarita [Pima Co], AZ USA [el. 882 m / 2893 ft]</span> <a href="http://maps.google.com/maps/ms?hl=en&ie=UTF8&t=h&msa=0&msid=100103460138962878270.000495438a2a2da766094&ll=31.900295,-110.996246&spn=0.204029,0.291824&z=11&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 11/06/10 10:01AM sunny, air temp: 24°C / 76°F</span>
<div class="captionImageMain">[IMAGE 1 of 2] Whenever we approached either of the two <a href="http://www.davidlouisquinn.com/pogolumina_PbicolorInfo.htm"><span class="glossLinkSm"><em>P. bicolor</em></span></a> nests at this location, one or two workers would immediately climb a grass stem and remain there, while appearing to watch us closely. Occasionally, the mandibles would be opened in a feeble defensive display. The rest of the workers (on the ground) went about their business, and ignored us completely. As mentioned earlier, the ants made no attempt to bite or <a href="http://www.davidlouisquinn.com/pogolumina_stingInfo.htm"><span class="glossLinkSm">sting</span></a>, no matter how closely we approached. The very fine and silky-looking <a href="http://www.davidlouisquinn.com/pogolumina_surfaceSculptureInfo.htm"><span class="glossLinkSm">surface sculpture </span></a> can also be seen in these images.</div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-QmVc5Z2/0/228f8876/Ti/6858_10_7Df-Ti.jpg)
![<span class="captionImageInfo"> ● Duval Mine Rd, Sahuarita [Pima Co], AZ USA [el. 882 m / 2893 ft]</span> <a href="http://maps.google.com/maps/ms?hl=en&ie=UTF8&t=h&msa=0&msid=100103460138962878270.000495438a2a2da766094&ll=31.900295,-110.996246&spn=0.204029,0.291824&z=11&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 11/06/10 9:01AM sunny, air temp: 21°C / 70°F</span>
<div class="captionImageMain">[IMAGE 2 of 2] Whenever we approached either of the two <a href="http://www.davidlouisquinn.com/pogolumina_PbicolorInfo.htm"><span class="glossLinkSm"><em>P. bicolor</em></span></a> nests at this location, one or two workers would immediately climb a grass stem and remain there, while appearing to watch us closely. Occasionally, the mandibles would be opened in a feeble defensive display. The rest of the workers (on the ground) went about their business, and ignored us completely. As mentioned earlier, the ants made no attempt to bite or <a href="http://www.davidlouisquinn.com/pogolumina_stingInfo.htm"><span class="glossLinkSm">sting</span></a>, no matter how closely we approached. The very fine and silky-looking <a href="http://www.davidlouisquinn.com/pogolumina_surfaceSculptureInfo.htm"><span class="glossLinkSm">surface sculpture </span></a> can also be seen in these images.</div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-ctJLpg6/0/fe52393c/Ti/6750_10_7D-Ti.jpg)
![<span class="captionImageInfo"> ● 6.4km/4mi SE of Oracle [Pinal Co], AZ USA [el. 1343 m / 4408 ft]</span> <a href="http://maps.google.com/maps/ms?hl=en&ie=UTF8&t=h&msa=0&msid=100103460138962878270.00049542e9e022431a362&ll=32.579221,-110.720215&spn=0.810036,1.167297&z=9&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 11/02/10 3:10PM sunny, air temp: 23°C / 73°F</span>
<div class="captionImageMain"> A <a href="http://www.davidlouisquinn.com/pogolumina_PbarbatusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex barbatus</em></span></a> worker menaces the photographer with open <a href="http://www.davidlouisquinn.com/pogolumina_mandiblesInfo.htm"><span class="glossLinkSm">mandibles</span></a>. This species, like many other <a href="http://www.davidlouisquinn.com/pogolumina_PogonomyrmexInfo.htm"><span class="glossLinkSm">Pogos</span></a>, will <a href="http://www.davidlouisquinn.com/pogolumina_stingInfo.htm"><span class="glossLinkSm">sting</span></a> readily (and painfully) with little provocation.](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-pp9d7Jh/0/2c16ae51/Ti/6320_10_7Dc-Ti.jpg)
![<span class="captionImageInfo"> ● Wanapum Rec. Area [Kittitas Co], WA USA [el. 190 m / 623 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.000470bd413e9e793ba1d&ll=46.905483,-119.9903&spn=0.164191,0.291824&z=11&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 5/16/10 11:50AM sun, haze, air temp: 26°C / 79°F</span>
Under the overhang of a lichen-covered boulder, an as yet unidentified male theridiid spider captures a <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex salinus</em></span></a> worker.](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-ccFcPvg/0/f5690429/Ti/3719_10_7Dc-Ti.jpg)
![<span class="captionImageInfo"> ● Horse Ridge, SE of Bend [Deschutes Co], OR USA [el. 1310 m / 4297 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.00047a3daca81cf459487&ll=43.912533,-121.007083&spn=0.086565,0.145912&z=12&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 7/20/09 7:14AM sunny, air temp: 11°C / 52°F </span>
<div class="captionImageMain">Unlike many other <a href="http://www.davidlouisquinn.com/pogolumina_PogonomyrmexInfo.htm"><span class="glossLinkSm">Pogo</span></a> species, a majority of the <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>P. salinus</em> </span></a> ants we encounter are very docile, and tolerate our presence with no signs of defensive behavior (usually ignoring us completely). Occasionally, however, we come across a colony populated by extremely pugnacious workers. On our first visit to this gigantic nest (July 2008) I was unable to approach the entrance, due to the many angry defenders. On the second visit (one year later - when this image was captured), we arrived when the temperature was still too low for the ants to be active, and waited for the first to emerge...
This worker was one of the first to come out. She stood in the sun just outside the entrance, and attempted to menace us with a feeble opening and closing of the <a href="http://www.davidlouisquinn.com/pogolumina_mandiblesInfo.htm"><span class="glossLinkSm">mandibles</span></a> (note the worn, blunt 'teeth'). At 11°C / 52°F, the air temperature was still too low for vigorous activity, though the rocky surface where this ant stood had already reached a surface temperature of approx. 20°C / 69°F. Facing east, this nest is constructed around large rocks which act as solar collectors - allowing its inhabitants to become active well before those of any other nest in the immediate vicinity that we have observed. Within an hour, many workers were active and becoming agitated, so I retreated. <span class ="footnoteTag">[scroll down for additional notes/references]</span>
</div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>On our first visit to this nest (7/15/08) the air temperature was 28°C / 82°F, and the ants were foraging along a trail in the shade of a large rock. Soon after I approached the entrance, many dozens of workers (defenders) poured out, and ran toward me. Most turned back after I backed away, but approximately 10 workers continued pursuing me more than 3.6 m / 12 ft from the entrance, often stopping to stand on small pebbles and twigs while waving their antennae wildly, and opening their mandibles.
At many other P. salinus nests nearby, workers were not aggressive, and ignored us - even when inches away from the entrances.
We think the physical size of the large nest (mentioned above), may have something to do with the very aggressive worker response to our presence. The gravel-covering of this nest was approx. 1.9 m / 76 in. wide, measured on its longest axis. This means that I had to walk over a large portion of the nest 'dome' in order to reach the entrance - undoubtedly collapsing many tunnels and galleries that lay just below the gravel covered surface. This would result in alarm pheromones being released in great quantities by the ants underfoot, alerting nestmates to the defense of their colony.</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-vT4mdwg/9/54624c60/Ti/0499_09_40f-Ti.jpg)
![<span class="captionImageInfo"> ● Wanapum Rec. Area [Kittitas Co], WA USA [el. 190 m / 623 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.000470bd413e9e793ba1d&ll=46.905483,-119.9903&spn=0.164191,0.291824&z=11&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 9/16/10 11:25AM 50% cloud, air temp: 26°C / 78°F</span>
<div class="captionImageMain">[IMAGE 1 of 4] When we arrived at this <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex salinus</em></span></a> nest in central Washington state, we immediately noticed several frantic <a href="http://www.davidlouisquinn.com/pogolumina_pheidoleWorkerInfo.htm"><span class="glossLinkSm">workers</span></a> using pebbles to block the nest entrance. It wasn't long before we saw the source of their distress; a <em>Clypeadon</em> digger wasp was preying upon these ants. In this image we see the predator on one of her visits to the <a href="http://www.davidlouisquinn.com/pogolumina_PogonomyrmexInfo.htm"><span class="glossLinkSm">Pogo</span></a> nest in search of prey. <span class ="footnoteTag">[scroll down for additional notes/references]</span>
</div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>Female digger wasps of the genus Clypeadon are known predators of <a href="http://www.davidlouisquinn.com/pogolumina_PogonomyrmexInfo.htm"><span class="glossLinkSm">Pogonomyrmex harvester ants</span></a>. Predation on <a href="http://www.davidlouisquinn.com/pogolumina_PoccidentalisInfo.htm"><span class="glossLinkSm">Pogonomyrmex occidentalis</span></a> workers by Clypeadon laticinctus wasps has been studied and documented in detail.
In the case of C. laticinctus, wasps typically land at an ant nest site, run up to an ant, grab it, then sting it. The paralyzed ant is then grasped by a special 'ant clamp' (modified pygidial plate and hypopigium) on the wasp's abdomen, and transported to the wasp's nest to be used as food for the developing larvae. The wasps' nests are in the form of burrows, excavated to depths of up to 25cm/10in, in sandy soils. There may be several brood chambers, each one packed with up to 26 ants. An egg is laid on the last ant put into the brood cell, then the cell is sealed up. The wasp larva will then consume the ants as it develops.
The hunting wasps will actually enter ant mounds to capture prey if ants are not present on the surface.
Ants will often turn to face the attacking wasp, and/or lunge at it. These tactics, along with the simple defense of running away, often result in an individual ant escaping capture. A 1984 study in Colorado showed that "approximately 63% of visits by wasps to ant mounds resulted in a successful prey capture." Despite their powerful mandibles and stings, Pogos have never been observed to injure or kill an attacking wasp.
Sometimes a wasp will sting a worker, then discard it before attacking and carrying away another ant. The reasons for this are not well understood, but there is some evidence that the wasps are selective, with larger individual ants being preferred.
Clypeadon wasps are members of the family Crabronidae, subfamily Philanthinae, and the tribe Aphilanthopini.
·Alexander, B. 1985. Predator-prey Interactions between the Digger Wasp Clypeadon laticinctus and the Harvester Ant Pogonomyrmex occidentalis. Journal of Natural History, 1985, 19:1139-1154<br>·Bohart, R.M. & A.S. Menke. 1976. Sphecid Wasps of the World: A Generic Revision. University of California Press, pp. 570-571<br>·Taber, S.W. 1998. The World of the Harvester Ants. College Station, TX, Texas A&M University Press
</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-fzHKJFw/0/e1564dd1/Ti/5831_10_7D-Ti.jpg)
![<span class="captionImageInfo"> ● Wanapum Rec. Area [Kittitas Co], WA USA [el. 190 m / 623 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.000470bd413e9e793ba1d&ll=46.905483,-119.9903&spn=0.164191,0.291824&z=11&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 9/16/10 11:22AM 50% cloud, air temp: 26°C / 78°F</span>
<div class="captionImageMain">[IMAGE 2 of 4] In this second image of the series, the <em>Clypeadon</em> wasp has run up to one of the <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>P. salinus</em></span></a> workers, and attacked it. The wasp's mandibles firmly hold the ant's head, while venom is injected via the sting on the end of the wasp's abdomen. It appeared that the ant may have been trying to sting back in defense, if so, it had no apparent effect on the wasp. <span class ="footnoteTag">[scroll down for additional notes/references]</span></div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>Female digger wasps of the genus Clypeadon are known predators of <a href="http://www.davidlouisquinn.com/pogolumina_PogonomyrmexInfo.htm"><span class="glossLinkSm">Pogonomyrmex harvester ants</span></a>. Predation on <a href="http://www.davidlouisquinn.com/pogolumina_PoccidentalisInfo.htm"><span class="glossLinkSm">Pogonomyrmex occidentalis</span></a> workers by Clypeadon laticinctus wasps has been studied and documented in detail.
In the case of C. laticinctus, wasps typically land at an ant nest site, run up to an ant, grab it, then sting it. The paralyzed ant is then grasped by a special 'ant clamp' (modified pygidial plate and hypopigium) on the wasp's abdomen, and transported to the wasp's nest to be used as food for the developing larvae. The wasps' nests are in the form of burrows, excavated to depths of up to 25cm/10in, in sandy soils. There may be several brood chambers, each one packed with up to 26 ants. An egg is laid on the last ant put into the brood cell, then the cell is sealed up. The wasp larva will then consume the ants as it develops.
The hunting wasps will actually enter ant mounds to capture prey if ants are not present on the surface.
Ants will often turn to face the attacking wasp, and/or lunge at it. These tactics, along with the simple defense of running away, often result in an individual ant escaping capture. A 1984 study in Colorado showed that "approximately 63% of visits by wasps to ant mounds resulted in a successful prey capture." Despite their powerful mandibles and stings, Pogos have never been observed to injure or kill an attacking wasp.
Sometimes a wasp will sting a worker, then discard it before attacking and carrying away another ant. The reasons for this are not well understood, but there is some evidence that the wasps are selective, with larger individual ants being preferred.
Clypeadon wasps are members of the family Crabronidae, subfamily Philanthinae, and the tribe Aphilanthopini.
·Alexander, B. 1985. Predator-prey Interactions between the Digger Wasp Clypeadon laticinctus and the Harvester Ant Pogonomyrmex occidentalis. Journal of Natural History, 1985, 19:1139-1154<br>·Bohart, R.M. & A.S. Menke. 1976. Sphecid Wasps of the World: A Generic Revision. University of California Press, pp. 570-571<br>·Taber, S.W. 1998. The World of the Harvester Ants. College Station, TX, Texas A&M University Press
</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-JTLwFpf/0/3875033c/Ti/5818_10_7Db-Ti.jpg)
![<span class="captionImageInfo"> ● Wanapum Rec. Area [Kittitas Co], WA USA [el. 190 m / 623 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.000470bd413e9e793ba1d&ll=46.905483,-119.9903&spn=0.164191,0.291824&z=11&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 9/16/10 11:23AM 50% cloud, air temp: 26°C / 78°F</span>
<div class="captionImageMain">[IMAGE 3 of 4] This image, taken just 12 seconds after the previous one, shows the now paralyzed <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>P. salinus</em></span></a> worker held firmly in the special 'ant clamp' on the wasp's abdomen. Seconds later, the <em>Clypeadon</em> wasp flew off with its prey. <span class="footnoteTag">[scroll down for additional notes/references]</span></div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>Female digger wasps of the genus Clypeadon are known predators of <a href="http://www.davidlouisquinn.com/pogolumina_PogonomyrmexInfo.htm"><span class="glossLinkSm">Pogonomyrmex harvester ants</span></a>. Predation on <a href="http://www.davidlouisquinn.com/pogolumina_PoccidentalisInfo.htm"><span class="glossLinkSm">Pogonomyrmex occidentalis</span></a> workers by Clypeadon laticinctus wasps has been studied and documented in detail.
In the case of C. laticinctus, wasps typically land at an ant nest site, run up to an ant, grab it, then sting it. The paralyzed ant is then grasped by a special 'ant clamp' (modified pygidial plate and hypopigium) on the wasp's abdomen, and transported to the wasp's nest to be used as food for the developing larvae. The wasps' nests are in the form of burrows, excavated to depths of up to 25cm/10in, in sandy soils. There may be several brood chambers, each one packed with up to 26 ants. An egg is laid on the last ant put into the brood cell, then the cell is sealed up. The wasp larva will then consume the ants as it develops.
The hunting wasps will actually enter ant mounds to capture prey if ants are not present on the surface.
Ants will often turn to face the attacking wasp, and/or lunge at it. These tactics, along with the simple defense of running away, often result in an individual ant escaping capture. A 1984 study in Colorado showed that "approximately 63% of visits by wasps to ant mounds resulted in a successful prey capture." Despite their powerful mandibles and stings, Pogos have never been observed to injure or kill an attacking wasp.
Sometimes a wasp will sting a worker, then discard it before attacking and carrying away another ant. The reasons for this are not well understood, but there is some evidence that the wasps are selective, with larger individual ants being preferred.
Clypeadon wasps are members of the family Crabronidae, subfamily Philanthinae, and the tribe Aphilanthopini.
·Alexander, B. 1985. Predator-prey Interactions between the Digger Wasp Clypeadon laticinctus and the Harvester Ant Pogonomyrmex occidentalis. Journal of Natural History, 1985, 19:1139-1154<br>·Bohart, R.M. & A.S. Menke. 1976. Sphecid Wasps of the World: A Generic Revision. University of California Press, pp. 570-571<br>·Taber, S.W. 1998. The World of the Harvester Ants. College Station, TX, Texas A&M University Press
</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-4RhWx32/0/901a5ed9/Ti/5823_10_7D-Ti.jpg)
![<span class="captionImageInfo"> ● Wanapum Rec. Area [Kittitas Co], WA USA [el. 190 m / 623 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.000470bd413e9e793ba1d&ll=46.905483,-119.9903&spn=0.164191,0.291824&z=11&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 9/16/10 10:57AM 50% cloud, air temp: 26°C / 78°F</span>
<div class="captionImageMain">[IMAGE 4 of 4 - see preceding 3 images] As mentioned in the notes below, these wasps often abandon an ant after stinging it, and capture a different one. Evidence suggests that the predators may prefer larger individual ants (there is considerable size variation among workers in a Pogo colony). This image shows a callow <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>P. salinus</em></span></a> worker that has apparently been stung and abandoned by the <em>Clypeadon</em> wasp. Pogos are known to cling to grass stems or twigs after being envenomated by other insects - you can see other examples of this elsewhere in the <em>'Defense, Aggression, and Pogos as Prey '</em> gallery. We also observed the wasp to sting and abandon a different worker at this nest; the partially paralyzed ant then staggered to the mostly-blocked nest entrance and disappeared inside. <span class ="footnoteTag">[scroll down for additional notes/references]</span>
</div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>Female digger wasps of the genus Clypeadon are known predators of <a href="http://www.davidlouisquinn.com/pogolumina_PogonomyrmexInfo.htm"><span class="glossLinkSm">Pogonomyrmex harvester ants</span></a>. Predation on <a href="http://www.davidlouisquinn.com/pogolumina_PoccidentalisInfo.htm"><span class="glossLinkSm">Pogonomyrmex occidentalis</span></a> workers by Clypeadon laticinctus wasps has been studied and documented in detail.
In the case of C. laticinctus, wasps typically land at an ant nest site, run up to an ant, grab it, then sting it. The paralyzed ant is then grasped by a special 'ant clamp' (modified pygidial plate and hypopigium) on the wasp's abdomen, and transported to the wasp's nest to be used as food for the developing larvae. The wasps' nests are in the form of burrows, excavated to depths of up to 25cm/10in, in sandy soils. There may be several brood chambers, each one packed with up to 26 ants. An egg is laid on the last ant put into the brood cell, then the cell is sealed up. The wasp larva will then consume the ants as it develops.
The hunting wasps will actually enter ant mounds to capture prey if ants are not present on the surface.
Ants will often turn to face the attacking wasp, and/or lunge at it. These tactics, along with the simple defense of running away, often result in an individual ant escaping capture. A 1984 study in Colorado showed that "approximately 63% of visits by wasps to ant mounds resulted in a successful prey capture." Despite their powerful mandibles and stings, Pogos have never been observed to injure or kill an attacking wasp.
Sometimes a wasp will sting a worker, then discard it before attacking and carrying away another ant. The reasons for this are not well understood, but there is some evidence that the wasps are selective, with larger individual ants being preferred.
Clypeadon wasps are members of the family Crabronidae, subfamily Philanthinae, and the tribe Aphilanthopini.
·Alexander, B. 1985. Predator-prey Interactions between the Digger Wasp Clypeadon laticinctus and the Harvester Ant Pogonomyrmex occidentalis. Journal of Natural History, 1985, 19:1139-1154<br>·Bohart, R.M. & A.S. Menke. 1976. Sphecid Wasps of the World: A Generic Revision. University of California Press, pp. 570-571<br>·Taber, S.W. 1998. The World of the Harvester Ants. College Station, TX, Texas A&M University Press
</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-P9SNbVX/0/a8a40e11/Ti/5742_10_7D-Ti.jpg)
![<span class="captionImageInfo"> ● Fernley [Lyon Co], NV USA [el. 1271 m / 4171 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.00048afd64f5e81bc4956&ll=39.614152,-119.262085&spn=1.481079,2.334595&z=8&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 6/23/10 6:36AM partly cloudy, air temp: 18°C / 64°F</span>
<div class="captionImageMain">A small <em>Dorymyrmex sp.</em> nest was located approximately 23 cm / 9 inches from the the nest of the <a href="http://www.davidlouisquinn.com/pogolumina_PcalifornicusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex californicus</em></span></a> worker seen here. Whenever a Pogo worker wandered near the smaller ants' nest, she would be harassed, and chased away. The Pogos were not observed to fight back - they simply ran a few inches away, and continued foraging. The <em>Dorymyrmex</em> workers were mostly performing maintenance on their nest, at the time these images were captured.
</div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-2j8LG5w/0/7f121535/Ti/4429_10_7Dc-Ti.jpg)
![<span class="captionImageInfo"> ● Boardman [Morrow Co], OR USA [el. 91m/298 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.00047a78918c03bd0a332&ll=45.850383,-119.692383&spn=0.669588,1.167297&z=9&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 7/22/09 8:06PM sunny, windy, air temp: 32°C / 89°F</span>
<div class="captionImageMain">[IMAGE 1 of 4] Ants of the genus <em>Tetramorium</em>, attacking and killing <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex salinus</em></span></a> workers, in central Oregon. <span class ="footnoteTag">[scroll down for additional notes/references]</span></div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>These Pogonomyrmex salinus workers, with their powerful mandibles and formidable stings, appeared to be defenseless against dozens of attacking Tetramorium ants (workers of Tetramorium species 'E', also known as pavement ants).
On a very warm July evening, we came upon this melee in progress. The westernmost entrance of a P. salinus nest (with at least three entrances total) was located approx. 20 cm / 8 in from a cryptic (difficult to see) Tetramorium nest entrance.
The pavement ants were attacking any Pogo that emerged from the above-mentioned entrance. They ran at, and stung the much larger Pogos, with incredibly quick movements (so quick, that we couldn't see exactly where they were delivering the sting).
The attacked Pogos twitched and writhed for a few moments, and then, without exception, clamped tightly onto a grass or other plant stem with their <a href="http://www.davidlouisquinn.com/pogolumina_mandiblesInfo.htm"><span class="glossLinkSm">mandibles</span></a>. A group of four to six Tetramorium workers surrounded each one of these afflicted Pogos, pulling on their legs and antennae (and in some cases removing these appendages, or parts of them) - or simply menacing them with open jaws. This looked a lot like the 'pinning down' behavior used by many ants to immobilize an intruder - but since the Pogos were already held fast, this seemed more like an attempt to kill, and dismember them. Tetramorium ants are well-known scavengers, so even if this began as a territorial war, it is likely they would take advantage of the killed Pogos, as a food source.
We saw two instances where a dying Pogo made a feeble attempt to defend herself with her mandibles - but we didn't see any Pogos actually inflict any damage on their assailants.
During the 'battle', a P. salinus head capsule with no antennae (or body), was observed still clinging to a grass stem, and a Tetramorium carrying the gaster (part of the abdomen) of a Pogo, was seen.
The next morning, we also saw pavement ants transporting detached P. salinus head capsules. Many Pogos still could be seen clinging to grass stems, some obviously dead, others moving slightly. The Pogo entrance at the center of all of this was blocked with debris at some point - probably by the Pogos themselves.
Curiously, during the height of the confrontation - foraging, and nest maintenance continued pretty much as usual at the main entrance to the Pogo nest, just .45 m / 1.5 ft away. No defense force was raised to come to the aid of those nestmates being attacked by the pavement ants. There was a strong wind blowing (from the main entrance, toward the site of the battle), and this may have prevented alarm pheromones from reaching the ants at the main entrance.</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-z7V6Fpb/5/ed3d039b/Ti/0853_09_40f-Ti.jpg)
![<span class="captionImageInfo"> ● Boardman [Morrow Co], OR USA [el. 91m/298 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.00047a78918c03bd0a332&ll=45.850383,-119.692383&spn=0.669588,1.167297&z=9&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 7/22/09 8:25PM sunny, windy, air temp: 29°C / 84°F</span>
<div class="captionImageMain">[IMAGE 2 of 4] Ants of the genus <em>Tetramorium</em>, attacking and killing <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex salinus</em></span></a> workers, in central Oregon. <span class ="footnoteTag">[scroll down for additional notes/references]</span></div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>These Pogonomyrmex salinus workers, with their powerful mandibles and formidable stings, appeared to be defenseless against dozens of attacking Tetramorium ants (workers of Tetramorium species 'E', also known as pavement ants).
On a very warm July evening, we came upon this melee in progress. The westernmost entrance of a P. salinus nest (with at least three entrances total) was located approx. 20 cm / 8 in from a cryptic (difficult to see) Tetramorium nest entrance.
The pavement ants were attacking any Pogo that emerged from the above-mentioned entrance. They ran at, and stung the much larger Pogos, with incredibly quick movements (so quick, that we couldn't see exactly where they were delivering the sting).
The attacked Pogos twitched and writhed for a few moments, and then, without exception, clamped tightly onto a grass or other plant stem with their <a href="http://www.davidlouisquinn.com/pogolumina_mandiblesInfo.htm"><span class="glossLinkSm">mandibles</span></a>. A group of four to six Tetramorium workers surrounded each one of these afflicted Pogos, pulling on their legs and antennae (and in some cases removing these appendages, or parts of them) - or simply menacing them with open jaws. This looked a lot like the 'pinning down' behavior used by many ants to immobilize an intruder - but since the Pogos were already held fast, this seemed more like an attempt to kill, and dismember them. Tetramorium ants are well-known scavengers, so even if this began as a territorial war, it is likely they would take advantage of the killed Pogos, as a food source.
We saw two instances where a dying Pogo made a feeble attempt to defend herself with her mandibles - but we didn't see any Pogos actually inflict any damage on their assailants.
During the 'battle', a P. salinus head capsule with no antennae (or body), was observed still clinging to a grass stem, and a Tetramorium carrying the gaster (part of the abdomen) of a Pogo, was seen.
The next morning, we also saw pavement ants transporting detached P. salinus head capsules. Many Pogos still could be seen clinging to grass stems, some obviously dead, others moving slightly. The Pogo entrance at the center of all of this was blocked with debris at some point - probably by the Pogos themselves.
Curiously, during the height of the confrontation - foraging, and nest maintenance continued pretty much as usual at the main entrance to the Pogo nest, just .45 m / 1.5 ft away. No defense force was raised to come to the aid of those nestmates being attacked by the pavement ants. There was a strong wind blowing (from the main entrance, toward the site of the battle), and this may have prevented alarm pheromones from reaching the ants at the main entrance.</em>
</div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-kMxdSDL/5/38d0abf4/Ti/0927_09_40f-Ti.jpg)
![<span class="captionImageInfo"> ● Boardman [Morrow Co], OR USA [el. 91m/298 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.00047a78918c03bd0a332&ll=45.850383,-119.692383&spn=0.669588,1.167297&z=9&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 7/22/09 8:30PM sunny, windy, air temp: 29°C / 84°F</span>
<div class="captionImageMain">[IMAGE 3 of 4] Ants of the genus <em>Tetramorium</em>, attacking and killing <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex salinus</em></span></a> workers, in central Oregon. <span class ="footnoteTag">[scroll down for additional notes/references]</span></div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>These Pogonomyrmex salinus workers, with their powerful mandibles and formidable stings, appeared to be defenseless against dozens of attacking Tetramorium ants (workers of Tetramorium species 'E', also known as pavement ants).
On a very warm July evening, we came upon this melee in progress. The westernmost entrance of a P. salinus nest (with at least three entrances total) was located approx. 20 cm / 8 in from a cryptic (difficult to see) Tetramorium nest entrance.
The pavement ants were attacking any Pogo that emerged from the above-mentioned entrance. They ran at, and stung the much larger Pogos, with incredibly quick movements (so quick, that we couldn't see exactly where they were delivering the sting).
The attacked Pogos twitched and writhed for a few moments, and then, without exception, clamped tightly onto a grass or other plant stem with their <a href="http://www.davidlouisquinn.com/pogolumina_mandiblesInfo.htm"><span class="glossLinkSm">mandibles</span></a>. A group of four to six Tetramorium workers surrounded each one of these afflicted Pogos, pulling on their legs and antennae (and in some cases removing these appendages, or parts of them) - or simply menacing them with open jaws. This looked a lot like the 'pinning down' behavior used by many ants to immobilize an intruder - but since the Pogos were already held fast, this seemed more like an attempt to kill, and dismember them. Tetramorium ants are well-known scavengers, so even if this began as a territorial war, it is likely they would take advantage of the killed Pogos, as a food source.
We saw two instances where a dying Pogo made a feeble attempt to defend herself with her mandibles - but we didn't see any Pogos actually inflict any damage on their assailants.
During the 'battle', a P. salinus head capsule with no antennae (or body), was observed still clinging to a grass stem, and a Tetramorium carrying the gaster (part of the abdomen) of a Pogo, was seen.
The next morning, we also saw pavement ants transporting detached P. salinus head capsules. Many Pogos still could be seen clinging to grass stems, some obviously dead, others moving slightly. The Pogo entrance at the center of all of this was blocked with debris at some point - probably by the Pogos themselves.
Curiously, during the height of the confrontation - foraging, and nest maintenance continued pretty much as usual at the main entrance to the Pogo nest, just .45 m / 1.5 ft away. No defense force was raised to come to the aid of those nestmates being attacked by the pavement ants. There was a strong wind blowing (from the main entrance, toward the site of the battle), and this may have prevented alarm pheromones from reaching the ants at the main entrance.</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-24wKgKM/2/e108d039/Ti/0941_09_40f-Ti.jpg)
![<span class="captionImageInfo"> ● Boardman [Morrow Co], OR USA [el. 91m/298 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.00047a78918c03bd0a332&ll=45.850383,-119.692383&spn=0.669588,1.167297&z=9&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 7/23/09 6:08AM sunny, windy, air temp: 20°C / 68°F</span>
<div class="captionImageMain">[IMAGE 4 of 4] Ants of the genus <em>Tetramorium</em>, attacking and killing <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex salinus</em></span></a> workers, in central Oregon. <span class ="footnoteTag">[scroll down for additional notes/references]</span></div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>These Pogonomyrmex salinus workers, with their powerful mandibles and formidable stings, appeared to be defenseless against dozens of attacking Tetramorium ants (workers of Tetramorium species 'E', also known as pavement ants).
On a very warm July evening, we came upon this melee in progress. The westernmost entrance of a P. salinus nest (with at least three entrances total) was located approx. 20 cm / 8 in from a cryptic (difficult to see) Tetramorium nest entrance.
The pavement ants were attacking any Pogo that emerged from the above-mentioned entrance. They ran at, and stung the much larger Pogos, with incredibly quick movements (so quick, that we couldn't see exactly where they were delivering the sting).
The attacked Pogos twitched and writhed for a few moments, and then, without exception, clamped tightly onto a grass or other plant stem with their <a href="http://www.davidlouisquinn.com/pogolumina_mandiblesInfo.htm"><span class="glossLinkSm">mandibles</span></a>. A group of four to six Tetramorium workers surrounded each one of these afflicted Pogos, pulling on their legs and antennae (and in some cases removing these appendages, or parts of them) - or simply menacing them with open jaws. This looked a lot like the 'pinning down' behavior used by many ants to immobilize an intruder - but since the Pogos were already held fast, this seemed more like an attempt to kill, and dismember them. Tetramorium ants are well-known scavengers, so even if this began as a territorial war, it is likely they would take advantage of the killed Pogos, as a food source.
We saw two instances where a dying Pogo made a feeble attempt to defend herself with her mandibles - but we didn't see any Pogos actually inflict any damage on their assailants.
During the 'battle', a P. salinus head capsule with no antennae (or body), was observed still clinging to a grass stem, and a Tetramorium carrying the gaster (part of the abdomen) of a Pogo, was seen.
The next morning, we also saw pavement ants transporting detached P. salinus head capsules. Many Pogos still could be seen clinging to grass stems, some obviously dead, others moving slightly. The Pogo entrance at the center of all of this was blocked with debris at some point - probably by the Pogos themselves.
Curiously, during the height of the confrontation - foraging, and nest maintenance continued pretty much as usual at the main entrance to the Pogo nest, just .45 m / 1.5 ft away. No defense force was raised to come to the aid of those nestmates being attacked by the pavement ants. There was a strong wind blowing (from the main entrance, toward the site of the battle), and this may have prevented alarm pheromones from reaching the ants at the main entrance.</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-qBCPFfP/4/37105ed2/Ti/0992_09_40f-Ti.jpg)
![<span class="captionImageInfo"> ● Wanapum Rec. Area [Kittitas Co], WA USA [el. 190 m / 623 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.000470bd413e9e793ba1d&ll=46.905483,-119.9903&spn=0.164191,0.291824&z=11&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 5/16/10 8:24AM sun/haze, air temp: 21°C / 70°F</span>
<div class="captionImageMain">An incoming <a href="http://www.davidlouisquinn.co/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex salinus</em></span></a> forager (left) is 'checked' by a nestmate, upon her return to the colony's home. <span class ="footnoteTag">[scroll down for additional notes/references]</span>
</div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>It is common to see workers waving their antennae over each other as they come and go around the nest entrance. Ants from the same colony have a distinctive odor (detectable by the ants) - and with a quick sweep of the antennae, a worker can chemically discriminate between a nestmate and an intruder. The ants can also receive and transmit important task, and status-related cues that help regulate foraging and other behaviors (including those concerning reproductive status). This is all facilitated by chemical compounds (hydrocarbons) that are produced within the ants' bodies, and that eventually reside on the outer layer of the ant's exoskeleton (cuticle). The frequent grooming by ants, of nestmates and themselves, helps distribute these nest/task/status-recognition labels throughout the colony.
·Greene, M.J. & D.M. Gordon. 2007. How Patrollers Set Foraging Direction in Harvester Ants. The American Naturalist, Vol. 170, No. 6, December 2007
·Hölldobler, B. & E.O. Wilson.1990. The Ants. Cambridge, MA, Belknap/Harvard Press
·Hölldobler, B. & E.O. Wilson. 2009. The Superorganism. W.W. Norton & Company, New York and London
·Wagner, D.,M. Tissot, W. Cuevas, and D.M. Gordon. 2000. Harvester Ants Utilize Cuticular Hydrocarbons in Nestmate Recognition. Journal of Chemical Ecology, Vol. 26, No. 10, 2000</em>
</div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-XJqdGxf/0/5d76fd4b/Ti/3513_10_7Df-Ti.jpg)
![<span class="captionImageInfo"> ● SW of Pyramid Lake [Washoe Co], NV USA [el. 1323 m / 4341 ft]</span> <a href="http://maps.google.com/maps/ms?hl=en&ie=UTF8&t=h&msa=0&msid=100103460138962878270.00048ab74785d385f672e&ll=39.800096,-119.665833&spn=0.738551,1.167297&z=9&source=embed"><span class="mapLink">view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 6/24/10 6:14AM mostly sunny, air temp: 12°C / 53°F</span>
<div class="captionImageMain">A <a href="http://www.davidlouisquinn.com/pogolumina_PoccidentalisInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex occidentalis</em></span></a> workers strikes a menacing pose. This was one of only two workers visible outside of the nest at this early hour. This species, like many other Pogos, will readily <a href="http://www.davidlouisquinn.com/pogolumina_stingInfo.htm"><span class="glossLinkSm">sting</span></a> intruders.
</div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-6BbjcMQ/0/e61e4b0a/Ti/4484_10_7Dc-Ti.jpg)
![<span class="captionImageInfo"> ● NW of Mattawa [Grant Co], WA USA [el. 152 m / 500 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.000470f37e319b015bf28&ll=46.7596,-119.932433&spn=0.329276,0.583649&z=10&source=embed"><span class="mapLink"> view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 5/17/09 7:08AM sunny, air temp: 14°C / 58°F</span>
<div class="captionImageMain">[IMAGE 1 of 2] Possibly as the result of fighting between members of two neighboring <a href="http://www.davidlouisquinn.com/pogolumina_PsalinusInfo.htm"><span class="glossLinkSm"><em>P.salinus</em></span></a> colonies, this <span class="glossLinkSm">worker</span></a> carries the detached head capsule of a conspecific (member of the same species) away from her nest. It was very early in the morning, and few workers were active yet - so if such a battle took place, it probably happened late on the previous day. We also found another <em>P.salinus</em> head capsule not far from this same nest <span class ="footnoteTag">[see next image]</span>. We also observed <em>P. salinus</em> workers fighting at this location one week earlier. <span class ="footnoteTag">[scroll down for additional notes/references]</span></div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>So far, we have seen few examples of intraspecific (involving members of the same species) combat occurring among P. salinus ants in the Pacific Northwest. For Pogos generally, these types of aggressive interactions usually take place when the foraging areas of neighboring colonies overlap, and individual foraging workers from the respective nests come into contact with one another. Established 'trunk-trails', and other habitual foraging routes that emanate from individual nest mounds, seem to be oriented to minimize contact (and therefore potentially aggressive interactions) between foraging workers from neighboring colonies in areas of high nest density. One study in southeast Idaho found that the foraging ranges of P. salinus seldom overlapped, nevertheless, these interactions do sometimes occur.
As we have observed, two P. salinus workers will occasionally engage in combat. Instances of this that we have witnessed, involved a sort of 'wrestling' - and both ants left apparently unharmed after disengagement (note: all examples witnessed by us have been in spring).
We have seen evidence after the fact, however, that these encounters sometimes result in fatalities, including a P. salinus worker with the head capsule of a conspecific still attached to its body, also, we have seen (and imaged) detached P. salinus head capsules in areas where we have previously, or subsequently observed these ants fighting. We often see (and image) P. salinus workers with partially missing/severed limbs - possibly as the result of intraspecific combat.
·Hölldobler, B.1974. Home Range Orientation and Territoriality in Harvesting Ants. Proceedings of the National Academy of Sciences USA, Vol. 71, No. 8, pp. 3274-3277, August 1974
·Hölldobler, B. & E.O. Wilson.1990. The Ants. Cambridge, MA, Belknap/Harvard Press
·Johnson, R.A. 2000. Seed Harvesting Ants (Hymenoptera: Formicidae) of North America: An Overview of Ecology and Biogeography. Sociobiology Vol.36, No. 1, 2000
·Jorgensen C.D. & Porter, S.D. 1982. Foraging Behavior of Pogonomyrmex Owyheei in Southest Idaho. Environmental Entomology, Vol. 11, No. 2, April 1982
</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-Sf6TRd9/3/5eb729f0/Ti/2140_09_Rc-Ti.jpg)
![<span class="captionImageInfo"> ● NW of Mattawa [Grant Co], WA USA [el. 152 m / 500 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.000470f37e319b015bf28&ll=46.7596,-119.932433&spn=0.329276,0.583649&z=10&source=embed"><span class="mapLink"> view location in Google Maps »</span></a>
<span class="captionImageInfo"> ● 5/17/09 7:12AM sunny, air temp: 14°C / 58°F</span>
<div class="captionImageMain">[IMAGE 2 of 2] Another detached <em>P. salinus</em> head capsule, found at the scene of possible intraspecific warfare. <span class ="footnoteTag">[scroll down for additional notes/references]</span></div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>So far, we have seen few examples of intraspecific (involving members of the same species) combat occurring among P. salinus ants in the Pacific Northwest. For Pogos generally, these types of aggressive interactions usually take place when the foraging areas of neighboring colonies overlap, and individual foraging workers from the respective nests come into contact with one another. Established 'trunk-trails', and other habitual foraging routes that emanate from individual nest mounds, seem to be oriented to minimize contact (and therefore potentially aggressive interactions) between foraging workers from neighboring colonies in areas of high nest density. One study in southeast Idaho found that the foraging ranges of P. salinus seldom overlapped, nevertheless, these interactions do sometimes occur.
As we have observed, two P. salinus workers will occasionally engage in combat. Instances of this that we have witnessed, involved a sort of 'wrestling' - and both ants left apparently unharmed after disengagement (note: all examples witnessed by us have been in spring).
We have seen evidence after the fact, however, that these encounters sometimes result in fatalities, including a P. salinus worker with the head capsule of a conspecific still attached to its body, also, we have seen (and imaged) detached P. salinus head capsules in areas where we have previously, or subsequently observed these ants fighting. We often see (and image) P. salinus workers with partially missing/severed limbs - possibly as the result of intraspecific combat.
·Hölldobler, B.1974. Home Range Orientation and Territoriality in Harvesting Ants. Proceedings of the National Academy of Sciences USA, Vol. 71, No. 8, pp. 3274-3277, August 1974
·Hölldobler, B. & E.O. Wilson.1990. The Ants. Cambridge, MA, Belknap/Harvard Press
·Johnson, R.A. 2000. Seed Harvesting Ants (Hymenoptera: Formicidae) of North America: An Overview of Ecology and Biogeography. Sociobiology Vol.36, No. 1, 2000
·Jorgensen C.D. & Porter, S.D. 1982. Foraging Behavior of Pogonomyrmex Owyheei in Southest Idaho. Environmental Entomology, Vol. 11, No. 2, April 1982
</em></div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-QmshS2f/3/a35335a7/Ti/2147_09_Rf-Ti.jpg)
![<span class="captionImageInfo"> ● Castolon [Loc 41] Big Bend N.P., TX USA [el. 660 m / 2164 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.00048384c67ef9deb4b45&ll=29.13417,-103.513355&spn=0.05248,0.072956&z=13&source=embed"><span class="mapLink"> view location in Google Maps »<span></a>
<span class="captionImageInfo"> ● 3/04/10 11:57AM sunny, air temp: 24°C / 76°F</span>
<div class="captionImageMain">Illuminated by the morning sun, a <a href="http://www.davidlouisquinn.com/pogolumina_PdesertorumInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex desertorum</em></span></a> worker 'freezes' in a defensive posture. This behavior was prompted by intruding <a href="http://www.davidlouisquinn.com/pogolumina_PrugosusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex rugosus</em></span></a> workers - one of which actually attacked a <em>P. desertorum</em> ant (both combatants walked away unharmed). <span class ="footnoteTag">[scroll down for additional notes/references]</span>
</div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>The integument (outer body covering) of these P. desertorum workers was quite translucent. When back-lit by the sun (as can be seen in some of these images), these ants glowed with the most beautiful orange-red color. In some cases, x-ray-like hints of their internal anatomy could be seen as well.
</em>
</div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-QZ79x6K/0/de748f0b/Ti/IMG_0865_7D_10c-Ti.jpg)
![<span class="captionImageInfo"> ● Castolon [Loc 41] Big Bend N.P., TX USA [el. 660 m / 2164 ft]</span> <a href="http://maps.google.com/maps/ms?ie=UTF8&hl=en&t=h&msa=0&msid=100103460138962878270.00048384c67ef9deb4b45&ll=29.13417,-103.513355&spn=0.05248,0.072956&z=13&source=embed"><span class="mapLink"> view location in Google Maps »<span></a>
<span class="captionImageInfo"> ● 3/06/10 10:45AM sun/haze, air temp: 18°C / 66°F</span>
<div class="captionImageMain">Another <a href="http://www.davidlouisquinn.com/pogolumina_PdesertorumInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex desertorum</em></span></a> worker frozen in a defensive posture, with mandibles (jaws) agape. We observed individuals remaining motionless like this for up to 10 minutes. As mentioned earlier, this heightened state of alert was due to intruding <a href="http://www.davidlouisquinn.com/pogolumina_PrugosusInfo.htm"><span class="glossLinkSm"><em>Pogonomyrmex rugosus</em></span></a> workers. These <em>P. desertorum</em> workers were extremely docile, and did seem to be concerned at all with our presence. <span class ="footnoteTag">[scroll down for additional notes/references]</span>
</div>
<div class="captionRefFootnote">ADDITIONAL NOTES/REFERENCES:
<em>The integument (outer body covering) of these P. desertorum workers was quite translucent. When back-lit by the sun (as can be seen in some of these images), these ants glowed with the most beautiful orange-red color. In some cases, x-ray-like hints of their internal anatomy could be seen as well.</em>
</div>](https://photos.smugmug.com/NorthAmericanPogosbyBehavior/Defense-Aggression-and-Pogos/i-WFxDpzQ/0/209e8868/Ti/IMG_2268_10_7Df-Ti.jpg)
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