Acute thermal effects in an inland freshwater crab Austrothelphusa transversa (von Martens, 1868) occupying seasonal, tropical rivers

Waltham, Nathan J. (2018) Acute thermal effects in an inland freshwater crab Austrothelphusa transversa (von Martens, 1868) occupying seasonal, tropical rivers. Journal of Crustacean Biology, 38 (4). pp. 497-503.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: http://doi.org/10.1093/jcbiol/ruy051
 
1


Abstract

Crustaceans occupying drying waterholes in seasonal tropical rivers can access terrestrial areas to regulate hyperthermia. An experiment tank filled with water and containing a mesh ramp and dry platform was designed to determine the terrestrial locomotion response of the tropical inland freshwater crab Australothelphusa transversa (von Martens, 1868) when exposed to increasing water temperatures. A thermoline controller increased water temperature (acclimation 25 °C, ± 0.5) at two rates, 18 °C h–1 (commonly employed in other studies) and 3 °C h–1 (reflecting measured regional river conditions) to determine the acute effects temperature (AET50) threshold for the crab. Random movement was minimal in the 18 °C h–1 experiment, with crabs accessing and remaining on the platform until the experiment ended (AET50 = 40.2; maximum = 41.69 °C). Crabs exhibited more random movement in the 3 °C h–1 experiment, visiting the platform for 3–21 min before returning for 3–131 min (AET50 = 34.2, maximum = 37.25 °C). Crabs collected from a second, more arid, geographical location in northern Australia had a similar AET using 3 °C h–1 increase (AET50 = 35.3; maximum 37.60 °C) and a similar AET using 18 °C h–1 increase (AET50 = 39.3; maximum 41.7 °C) to the coastal crab results (ANCOVA interaction location and ramp rate F = 1.88, P > 0.15). A temperature rate altering AET estimates by several degrees (regardless of where crab population was collected: ANCOVA location, F = 0.668, P > 0.4; rate increase factor, F = 4.31, P < 0.001) highlights the need for laboratory experiments to be underpinned by relevant field data. These data outline that crab avoidance responses could include accessing river banks, as a response necessary to regulate temperature during critical periods.

Item ID: 54855
Item Type: Article (Research - C1)
ISSN: 1937-240X
Keywords: freshwater crabs, tropics, freshwater ecology, crustaceans
Funders: James Cook University (JCU)
Date Deposited: 14 Aug 2018 01:41
FoR Codes: 06 BIOLOGICAL SCIENCES > 0602 Ecology > 060204 Freshwater Ecology @ 40%
05 ENVIRONMENTAL SCIENCES > 0502 Environmental Science and Management > 050202 Conservation and Biodiversity @ 30%
05 ENVIRONMENTAL SCIENCES > 0502 Environmental Science and Management > 050205 Environmental Management @ 30%
SEO Codes: 96 ENVIRONMENT > 9608 Flora, Fauna and Biodiversity > 960807 Fresh, Ground and Surface Water Flora, Fauna and Biodiversity @ 50%
96 ENVIRONMENT > 9606 Environmental and Natural Resource Evaluation > 960604 Environmental Management Systems @ 50%
Downloads: Total: 1
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page