Prairie Mole Cricket

Description

Gryllotalpa major,also known as the Prairie Mole Cricket, is endemic to the United States and is the largest cricket in North America. Its natural habitat is temperate grassland and it belongs to the family Gryllotalpidae. It is threatened by habitat loss, and is currently only found in Oklahoma, Kansas, Missouri, Nebraska and Arkansas. Males of this species produce sounds by rubbing their fore wings together. They sing from special burrows they construct in the prairie soil to attract females for mating, and they can be heard at distances up to 400 m from the burrow. Males aggregate their acoustic burrows in a lek arena and are very sensitive to vibrations carried through the ground. Males communicate with neighboring males through vibrational signals, and the songs they project to flying females are harmonic chirps, rather than the trills produced by most mole crickets. G. major is native to tall grass prairie ecosystems and occupies a small range in the southcentral United States, found only in Kansas, Missouri, Arkansas, and Oklahoma. Prescribed burning is common throughout the prairie habitat of G. major and usually occurs during March and April, at the begging of the reproductive season of the cricket. Howard and Hill looked to the effect of these burning on the distribution of G. major and found that recent burned land can be beneficial to the cricket and provide some advantages to mating behaviours. G. major has been observed calling on recently burned sites within 24 hours of the site being burned. The warmer soil as a result of the fire is thought to have metabolic advantages for the cricket, allowing them to increase their chirp frequency, and overall the burned land allows their song to travel more efficiently, increasing to attraction of females to the area. The belowground grass biomass on which the cricket feeds remains intact after a burn, and no evidence of direct mortality of the cricket has been documented. The grass height of the prairie land has a marked effect on the male burrows in a lek. They found that as grass height increased, the spacing between each burrow also increased, as well as an increase in the angle of opening to the burrow. This behavior may have evolved as response to the dynamic disturbances of tallgrass prairie ecosystems.