Lyons, P.J.

Recent research by CIEE Research Station Bonaire led by Dr. Patrick Lyons examined the effects of recreational SCUBA divers on the abundance of different types of sessile organisms (massive stony corals, branching stony corals, sponges, etc). The researchers also examined whether divers affect the structural complexity of coral reefs, a key element that makes reefs so diverse.  

News article on:

Lyons, P.J., E. Arboleda, C.E. Benkwitt, B. Davis, M. Gleason, C. Howe, J. Mathe, J. Middleton, N. Sikowitz, L. Unter- steggaber, S. Villalobos (2015) The e ect of recreational SCUBA divers on the structural complexity and benthic assemblage of a Caribbean coral reef, Biodiversity and Conservation 24(14): 3491-3504 

This news article was published in BioNews 20

BioNews is produced by the Dutch Caribbean Nature Alliance and funded by the Ministry of Economic Affairs.

Abstract

The effect of recreational SCUBA diving on coral reefs is likely secondary to many of the commonly cited stressors that threaten the long-term survival of coral reefs, such as rising temperatures. However, recreational SCUBA diving has had documented effects on various benthic organisms. Most research on the effect of SCUBA divers has focused on broken and abraded benthic organisms or the rate at which divers contact the benthos. We tested for differences in the structural complexity and benthic assemblage between pairs of heavily and lightly trafficked dive sites in Bonaire, a popular Carribbean diving destination. There was roughly 10 % less structural complexity in areas of heavy traffic. This is alarming given that the structural complexity of shallow reefs in Bonaire is substantially lower than in the 1970s. Different functional groups of benthic organisms were affected differentially by diving traffic. For instance, massive corals such as Orbicella annularis were 31 % less abundant at heavy than light diver traffic areas, while gorgonians and sponges had similar abundances at heavy and light diver traffic areas. Our results match those of previous studies on the resistance and resilience of tropical benthic reef organisms to physical disturbances that suggest that stony corals are more prone to physical damage than gorgonians and sponges. We provide a number of possible management strategies that could reduce the effects of recreational SCUBA divers on Bonaire and elsewhere, including education/intervention by dive guides and concentration of diving traffic away from areas of stony coral abundance.

Field and laboratory observations of feeding by invasive Pacific red lionfish Pterois volitans were conducted during June through August of 2008, 2009 and 2010 near Lee Stocking Island, Bahamas. Observations of this invasive marine predator revealed a previously undocumented piscivorous behavior. While slowly approaching prey fish, lionfish produce jets of water directed toward their prey. These jets may confuse or distract prey, and often result in prey fish facing the attacking lionfish, increasing the probability of head-first capture and swallowing. While a variety of fishes are re - ported to create directed water jets, to our knowledge, this is the first report of a fish that does so during the capture of fish prey. This behavior may confer a high degree of predatory efficiency, and thus contribute to the dramatic success of this Pacific invader of tropical Western Atlantic and Caribbean coral reefs