Microhabitat selection by adult puritan tiger beetles (cicindela puritana) and human recreation in Massachusetts

Abbott, Brandon R.
Jon Atwood, PhD
Department of Environmental Studies
Cicindela puritana, the Puritan tiger beetle, is a federally threatened species that inhabits shoreline beaches along the Connecticut River in Massachusetts and Connecticut and along the Chesapeake Bay in Calvert County Maryland (Knisley 1987; U.S. Fish and Wildlife Service 1993). The Massachusetts population has been estimated at less than 50 adults since standard survey efforts began in 1997 (Davis 2001a) and remains threatened with local extirpation. The primary site where the Massachusetts population occurs, Rainbow Beach in Northampton, is used for human recreation during summer months, and these activities may be impacting adult C. puritana foraging and mating activities. I assisted with capturing, marking, and resighting adult C. puritana during the summer of 2002. I documented habitat locations for each C. puritana capture and resight, and I measured microhabitat characteristics at 66 sites where adult C. puritana were captured or resighted, as well as at 67 randomly selected sites distributed throughout the beach. Levels of human recreation were documented during week days and weekend days, and I compared areas used for recreation with areas where adult C. puritana were observed. Forty-six percent of observed adult C. puritana were in habitat sections 2 and 3. Measured microhabitat sites where adult C. puritana were observed were a mean distance of 3.9 m to the Connecticut River, had minimal to no vegetation (mean % cover = 0.01), and had a mean substrate surface temperature of 35.8 ºC. Human recreation was low to moderate during week days, and moderate to heavy during weekend days: approximately 94.9% of activities occurred within 10 m of the shoreline. A total of 112 adult C. puritana were counted from July 1 to August 9, 2002, but a low larval count in fall 2002 suggests that reproductive success or embryonic and first instar survivorship was low this year. The inevitable interactions between human recreations users and adult C. puritana may be limiting the recovery of this species in Massachusetts. Further research is recommended.

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