Abstract Detail

Recent Topics Posters

Erickson, Amy Anne [1], Feller, Ilka [2], Paul, Valerie [3], Kwiatkowski, Lisa [4], Lee, Woody [4].

Selection of an omnivorous diet by the mangrove tree crab Aratus pisonii in laboratory experiments.

Studies on leaf damage, gut content analyses, and crab behavior have demonstrated that like numerous other mangrove and salt-marsh generalists, the mangrove tree crab Aratus pisonii feeds on a variety of food resources.  This study is the first to experimentally test feeding preferences of A. pisonii and test whether chemical composition of food resources is responsible for food selection.  Feeding preferences were determined among a variety of plant, algal, and animal resources available in the field in Florida and Belize, using multiple–choice feeding assays, where crabs simultaneously were offered a variety of food items.  To test whether chemistry of food resources was responsible for feeding preferences, chemical extracts of food resources were incorporated in agar-based artificial food which was then used in feeding assays.  Feeding assays suggested that crabs prefer animal matter anywhere from 2.5 to 13 times more than other available resources, including leaves of the red mangrove Rhizophora mangle, which comprise a significant part of their natural diet.  Feeding assays with extracts also demonstrated that chemical cues were responsible for selection of animal matter, up to 25 times more than other available resources.  Non-polar extracts stimulated feeding the most, suggesting that fatty acids, triglycerides, or sterols may be important for growth, reproduction, or survival.  Results for both sexes were similar across most assays.  While chemical composition of food resources influences selection, this does not discount the potential of other factors, such as resource availability, competition, predation, or reproductive requirements to influence feeding preferences as well.  

Broader Impacts:

1 - Louisiana State University Shreveport, Biological Sciences, One University Place, Shreveport, LA, 71115, USA
2 - Smithsonian Environmental Research Center, 647 Contees Wharf Rd., Edgewater, MD, 21037, USA
3 - Smithsonian Marine Station at Fort Pierce, 701 Seaway Dr., Fort Pierce, FL, 34949, USA
4 - Smithsonian Marine Station at Fort Pierce, 701 Seaway Dr., Fort Pierce, FL, 34949, USA

Keywords:
herbivory
feeding preferences
mangroves
omnivory
chemical ecology.

Presentation Type: Recent Topics Poster
Session: P
Location: Grand Salon A - D/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 5:30 PM
Number: PRT018
Abstract ID:1307
Candidate for Awards:None