Gulf of Mexico

Neotype for Coenobita clypeatus (Fabricius, 1787)
Catalog Number: USNM 126773
Collection: Smithsonian Institution, National Museum of Natural History, Department of Invertebrate Zoology
Sex/Stage: male;
Preparation: Alcohol (Ethanol)
Collector(s): R. Zusi
Year Collected: 1964
Locality: Batali River, North of Grande Savane, North of Salisbury, Dominica
Elevation (m): 61 to 61

Depth range based on 9 specimens in 1 taxon.
Water temperature and chemistry ranges based on 2 samples.

Environmental ranges
  Depth range (m): 0.5 - 80
  Temperature range (°C): 26.410 - 27.654
  Nitrate (umol/L): 1.786 - 2.120
  Salinity (PPS): 36.041 - 36.287
  Oxygen (ml/l): 4.616 - 4.658
  Phosphate (umol/l): 0.093 - 0.185
  Silicate (umol/l): 1.726 - 1.986

Graphical representation

Depth range (m): 0.5 - 80

Temperature range (°C): 26.410 - 27.654

Nitrate (umol/L): 1.786 - 2.120

Salinity (PPS): 36.041 - 36.287

Oxygen (ml/l): 4.616 - 4.658

Phosphate (umol/l): 0.093 - 0.185

Silicate (umol/l): 1.726 - 1.986
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Hermit crab shell-switching patterns have been used as case studies in vacancy chain theory (Lewis and Rotjan 2009), a body of theory originally developed by sociologists to understand how vacancies involving discrete, reusable, and limited resources such as apartments, jobs, and cars are transferred within human populations. When an individual gets a new resource, the vacancy thus created can propagate down the socioeconomic order through a series of interdependent events, with the result that many individuals can benefit “downstream” through the acquisition of new physical resources or social positions. Rotjan et al. (2010) describe 2 types of hermit crab vacancy chains, synchronous and asynchronous. These 2 types of vacancy chains are both social and stand in direct contrast to solitary shell interactions involving a single crab and a single shell. Synchronous vacancy chains occur after several crabs adjacent to an available vacant shell have queued in decreasing size order; as soon as the largest crab switches into the vacant shell, a rapid series of sequential shell switches takes place. In contrast, in asynchronous vacancy chains individual crabs encountering a suitable vacant shell will switch and their discarded shells will later be discovered and occupied by other crabs. Thus, asynchronous vacancy chains do not involve social interactions or queue formation, and sequential shell switches take place over considerably longer time periods. In both cases, vacancy chains are terminated when the last shell discarded is of such low quality (too small or damaged) that all crabs reject it. In field observations, Rotjan et al. (2010) found that after investigation of a vacant shell that was too large, hermit crabs would remain near (within 50 cm) the shell rather than moving away immediately: crab waiting times ranged from several minutes to more than an hour, and up to 20 waiters at a time were present near the empty shell. Crabs exhibited waiting behavior at 55% (6 of 11) of stations with large vacant shells and at 100% (9 of 9) of stations with medium vacant shells. Waiters were observed at all stations where synchronous vacancy chains eventually occurred. (Rotjan et al. 2010 and references therein)

Social networking aids housing search: hermit crabs
 

Social networking behaviors in hermit crabs helps them find new homes using vacancy chains and other behaviors.

       
 
  Learn more about this functional adaptation.