User:Sandcraby16/Profilicollis altmani

Profilicollis altmani is a species of Acanthocephalan parasite. This parasite first develops in the hindgut of mole crabs, species Emerita analoga and Emerita talpoida along the east and west coasts of the United States. After infection of the mole crab (the intermediate host), the parasite becomes a dormant cystacanth until the crab is eaten by a suitable bird, such as the Surf Scoter Melanitta perspicillata or Herring Gull, Larus argentatus (the final or definitive host). Once the parasite cystacanth has passed through the stomach of the bird, it develops into the adult worm and attaches to the intestines of the bird. Eggs produced by the parasite are released from the bird with bird feces and enter the ocean. Here the eggs are transported by the currents until they are accidentally ingested by a filter-feeding mole crab.

Another species of Acanthocephalan, Profilicollis kenti has also been listed as infecting mole crabs but recent research on the morphology of this species suggests that it is not a separate species from Profilicollis altmani.

Interestingly, Profilicollis altmani has become the subject of increasing research as it has been discovered that this parasite is contributing to a substantial proportion of the deaths of the southern sea otter, Enhydra lutris nereis. Between 1998 and 2001, between 13% and 16.2% of sea otter carcasses found around central California the cause of death was determined to be a direct result of acanthocephalan peritonitis, caused by this species of parasite. Several decades ago, the proportion of sea otters dying because of these parasites was almost negligible. Most of the sea otters that were found to be killed by infections by Profilicollis altmani were either young juvenile or older female otters, and it is hypothesized that they feed on sand crabs because they are less skilled at foraging or because of a decrease in their preferred prey.