bassianolide and Barotrauma

Previous studies exploring injury response to pile driving in fishes presented exposure paradigms (>900 strikes) that emulated circumstances where fish would not leave an area being ensonified. Those studies did not, however, address the question of how many strikes are needed before injuries appear. Thus, the number of strikes paired with a constant single strike sound exposure level (SEL

Topics: Air Sacs; Animals; Barotrauma; Bass; Ecosystem; Environmental Exposure; Environmental Monitoring; Noise; Oceans and Seas; Risk Assessment; Risk Factors; Swimming

The effects of loud sounds on fishes, such as those produced during impulsive pile driving, are an increasing concern in the management of aquatic ecosystems. However, very little is known about such effects. Accordingly, a High Intensity Controlled Impedance Fluid Filled wave Tube (HICI-FT) was used to investigate the effects of sounds produced by impulsive pile driving on two size groups of hybrid striped bass (white bass Moronechrysops x striped bass Moronesaxatilis). The larger striped bass (mean size 17.2 g) had more severe injuries, as well as more total injuries, than the smaller fish (mean size 1.3 g). However, fish in each size group recovered from most injuries within 10 days of exposure. A comparison with different species from previously published studies show that current results support the observation that fishes with physoclistous swim bladders are more susceptible to injury from impulsive pile driving than are fishes with physostomous swim bladders.

Topics: Analysis of Variance; Animals; Barotrauma; Bass; Ecosystem; Risk Factors; Sound

The effects of barotrauma on the short-term mortality and physical condition of Australian bass Macquaria novemaculeata were investigated after being: (1) conventionally angled and released during two tournaments in deep impoundments and (2) released untreated or subjected to venting or recompression during a manipulative experiment. All fish were released into two 20 m deep bathy-cages and monitored for 3 days. Of 238 M. novemaculeata angled during the tournaments, 43 (18·1%) had clinical signs of barotrauma or were vented and five of these later died (11·6% mortality). Catch histories varied significantly between both barotrauma and non-barotrauma fish and tournaments, but only hook ingestion significantly influenced mortality (P < 0·05). During the manipulative experiment, venting significantly influenced mortality (13·3%) compared to no treatment or recompression (no deaths). Magnetic resonance images and dissections of barotrauma fish indicated large variation among clinical signs. On the basis of these results, wherever possible M. novemaculeata suffering barotrauma should be immediately released with no treatment. Fish that are unable to resubmerge should be recompressed, while those held in live wells and released in shallow water should be vented.

Topics: Animals; Australia; Barotrauma; Bass; Fisheries; Handling, Psychological; Recreation; Stress, Physiological; Temperature