Laboratory replication of Devils Hole algal and zooplankton communities

Authors: Justin Mapula, Olin G. Feuerbacher, Scott A. Bonar, Kevin P. Wilson

Year: 2009 (xli)

Abstract

The Devils Hole Pupfish, Cyprinidon diabolis, is a relic of the last ice age; stranded as receding glacial lakes moved across a drying and warming landscape. Recent, dramatic declines in the Devils Hole Pupfish population have raised concerns over the future of the species. As there are no remaining refugia for pure-strain pupfish outside of Devils Hole, the possibility of extinction has become quite real. Previous lack of success for rearing fish in laboratory settings coupled with low egg viability further complicate recovery efforts. Census divers and scientists associated with the Devils Hole program have reported sighting larval pupfish on the stone shelf, as well as adult fish throughout the upper reaches of the water column. However, there are few reports of middle-age class fish, and with numbers of adults that are significantly lower than previous years, it seems that many larval fish are simply not surviving to the adult age class. Through these gradual changes, marked differences have been observed in the natural algal and invertebrate communities. In hope of aiding recovery efforts, we have begun cultures of algae and zooplankton species native to Devils Hole, which will be stocked into a 3000-gallon mesocosym designed to provide maximum control over both biotic and abiotic features. The design of this system will simulate a natural ecosystem while allowing for growth of plankton and larval fish. It also allows for microscale monitoring and control over community dynamics to simulate Devils Hole over different seasons and different decades and is applicable to simulation of other ecological models.