Coping with Invasive Invaders: Behavioral and Morphological Modifications of the Texas Horned Lizard (pp. 159-176)
Authors: (Scott E. Henke, Texas A&M University-Kingsville, TX, USA)
Abstract: Texas horned lizards (Phrynosoma cornutum) were once numerous and widely distributed across the south central United States. Their numbers have drastically declined and their distribution has become patchy presumably due to past over-collection, use of broadcast pesticides, urban and suburban sprawl, habitat loss to agriculture, and the introduction of invasive species. Recent attempts to translocate Texas horned lizards from viable populations to areas of suitable habitat demonstrate that translocation is not a feasible option. However, Texas horned lizard numbers are rebounding in certain areas within their former distribution because they have adapted to some of the environmental conditions that potentially resulted in their decline. Texas horned lizards have become commensal with humans and can be found within suburban areas of Kenedy, Lubbock, and McAllen, Texas, for example. They also have developed strategies to cope with attacks by the invasive red imported fire ant (Solenopsis invicta), and have learned to use certain invasive grass species (i.e., buffelgrass, Pennisetum ciliare ) to their advantage as hiding cover. Although such adaptations have aided the Texas horned lizard recovery, this Texas icon reptile still has a long way to go to return to its former abundance and distribution.