LTER Network Fiddler Crab Burrow Microbiomes
The Atlantic marsh fiddler crab (Minuca pugnax), along with other fiddlers, are ecosystem engineers who dig burrows in salt marsh sediments. These burrows create mechanisms for oxygen to get into what would otherwise be anoxic soil, thereby potentially altering the geochemistry of the marsh sediment. M. Pugnax is also a climate migrant, and has expanded beyond its historic northern range limit of Cape Cod, MA. To assess whether fiddler crabs shift microbial communities in similar ways throughout their historic and expanding ranges, we collected sediments from within and adjacent to crab burrows from four long-term ecological research sites along the east coast of the United States. We also collected co-occurring data on soil chemistry, gas flux, and food webs to examine how these ecosystem engineers are altering their surroundings as they expand their range.