Songbirds have many predators such as cats, hawks, and falcons. However few people know there is actually a songbird that preys on other songbirds! I am referring to the Loggerhead Shrike, Lanius ludovicianus, which feeds on insects, lizards, amphibians, small mammals, and other songbirds.

Upon first sight one could hardly believe that these birds are vicious predators. Weighing in at only 35-50 g (1.2-1.8 oz) these grey and black birds do not appear to be that formidable. However these small songbirds have several adaptations that have allowed them to become very successful predators, even capable of taking down other songbirds.

These birds have a hooked bill, similar to that of raptors like falcons and hawks, designed to hold onto the flesh of their prey. They also have a strong notch or “tooth” with which they can sever the spine of their victims. Unlike raptors they lack strong talons to hold onto their prey though. This is not a problem for these clever little birds. To overcome this inconvenience these shrikes have found a behavioral adaptation. Instead of holding their prey down to tear chunks of flesh away they will impale their prey on something. Often this will be a sturdy thorn or a barded wire fence. Some have even been seen using Joshua trees to hold their prey.

These birds have even found a way to overcome a common problem faced by all predators, prey shortages. While the hunting is good, these birds will kill more insects, songbirds, or small mammals than they could actually eat at the time. These are then stored, impaled on a spike, to provide food in case prey becomes scarce.

This is the only species of the family Laniidae (true shrikes) that is found exclusively in North America. Like many North American birds these interesting shrikes are currently in a state of decline. However, with the exception of the sub-species on San Clemente Island in California, this species is still designated as a species of least concern by the IUCN as their total numbers are still greater than 10,000 individuals. The reasons for the decline are currently not well understood. Habitat alterations (such as the conversion of pastures to croplands and urbanization) along with the use of pesticides are thought to be key players in the downward trend. On a positive note, conservation efforts of the San Clemente sub-species have increased the numbers of this group from 14 individuals in 1990 to 46 pairs and 100 juveniles in 2009.

Loggerhead Shrike Photo

 

Range Map:

References:

http://www.allaboutbirds.org/guide/Loggerhead_Shrike/lifehistory

http://www.arkive.org/loggerhead-shrike/lanius-ludovicianus/

http://www.iucnredlist.org/details/full/106005537/0

Photos courtesy of:

http://decorumforum.blogspot.com/2012/01/loggerhead-or-northern-or-not-shrike-at.html

http://featheredphotography.com/blog/2011/06/10/antelope-island-potpourri/

http://www.allaboutbirds.org/guide/Loggerhead_Shrike/id

 

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