Observation of a Semi-Aquatic Spider Attack: An Overlooked Fish Predator in a Well-Studied Ecosystem?

Amy E. Deacon, Aidan D. Farrell, Douglas F. Fraser


We describe here a noteworthy spider encounter that took place on the bank of the Ramdeen Stream in Trinidad's Arima Valley (10°41'32"N; 61°17'36"W) on 23 August, 2014. This stream forms part of one of the most intensively-studied freshwater ecosystems in the tropics; for more than four decades international researchers have been visiting this valley to discover more about the ecology and evolution of the fishes that it supports - primarily the Trinidadian guppy Poecilia reticulata and the killifish Rivulus hartii (recently revised as Anablepsoides hartii). This unrivalled body of research has greatly expanded our understanding of natural selection, evolution and community ecology (Magurran 2005).

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Bhukal, R., Rutherford, M.G. and Mohammed, R.S. 2015. Predation on a Freshwater Crab, Dilocarcinus dentatus by Several Tropical Wolf Spiders, Ancylometes bogotensis (Ctenidae) in Trinidad, W.I. Living World, Journal of The Trinidad and Tobago Field Naturalists’ Club, 2015: 59-60.

Brzostowicz, F. and Greven, H. 2007. Beobachtungen an der Fischerspinne Ancylometes bogotensis Keyserling, 1877 (Araneae). Acta Biologica Benrodis, 14, 39-54.

Croft, D.P., Morrell, L.J., Wade, A.S., Piyapong, C., Ioannou, C.C., Dyer, J.R.G., Chapman, B.B., Wong, Y. and Krause, J. 2006. Predation Risk as a Driving Force for Sexual Segregation: A Cross-Population Comparison. The American Naturalist, 167: 867-878.

Dugatkin, L.A. and Godin, J.G.J. 1992. Predator Inspection, Shoaling and Foraging under Predation Hazard in the Trinidadian Guppy Poecilia reticulata. Environmental Biology of Fishes, 34: 265-276.

Fraser, D.F. and Lamphere, B.A. 2013. Experimental evaluation of predation as a facilitator of invasion success in a stream fish. Ecology, 94: 640-649.

Gibb, A.C., Ashley-Ross, M.A., Pace, C.M. and Long, J.H. 2011. Fish out of water: terrestrial jumping by fully aquatic fishes. Journal of Experimental Zoology Part A: Ecological Genetics and Physiology, 315A: 649-653.

Höfer, H. and Brescovit, A.D. 2000. A revision of the Neotropical spider genus Ancylometes Bertkau (Araneae: Pisauridae). Insect Systematics and Evolution, 31: 323-360.

Magurran, A.E. 2005. Evolutionary Ecology: The Trinidadian Guppy. Oxford, Oxford University Press.

Nyffeler, M. and Pusey, B.J. 2014. Fish predation by semi-aquatic spiders: A global pattern. PLoS ONE, 9, e99459.

Rasband, W.S. 1997-2014. ImageJ, U.S. National Institutes of Health, Bethesda, Maryland, USA. http://imagej nih.gov/ij/, 1997-2014.

Sewlal, J.A.N. and Cutler, B. 2003. Annotated list of spider families (Araneida) of Trinidad and Tobago. Living World, Journal of The Trinidad and Tobago Field Naturalists’Club, 2003: 9-13.

Sewlal, J.N. 2013. Checklist of Trinidad and Tobago spider families. [Online]. Available at: http://www.caribbeanspiders.com/checklist_of_spiders_in_trinidad htm (Accessed 10 July, 2015).

White, G. 2015. Observation of a spider, Ancylometes bogotensis (Ctenidae), preying on the frog Rhinella beebei (Bufonidae) in Trinidad. Living World, Journal of The Trinidad and Tobago Field Naturalists’ Club, 2015:61-62.