Ecological Energetics


Ecological energetics is the study of the flow of energy through populations and the processes leading to these changes in state and location of matter and energy. When an organism consumes a meal it is digested, some of the matter and energy are assimilated into the animal and used for maintenance, growth, or reproduction. Some of the matter and energy are lost through excretion. By understanding these processes in the individual they can be extrapolated up to a whole population and used to construct food-web models for whole communities. 




Research in this theme has involved experiments in the laboratory on deep-sea fishes to study assimilation efficiencies and the development of a high pressure retaining fish trap to capture delicate deep-sea fishes on the deep-sea floor and  return them to the surface under pressure and at cold temperatures. Biochemical techniques utilizing the activity of metabolic enzymes and assays for the composition of fish tissues have also been utilized. Most recently, through NSF funding, in situ chambers to measure fish metabolism are being built. 



Most experiments to measure digestion efficiency, metabolism and other energetic processes occur in a laboratory setting. Because deep-sea animals do not typically survive capture and return to the surface, there is very little data on their ecological energetics. Ongoing research in the lab aims to fill this gap in our knowledge to gain a better understanding of energetics in general and to apply this knowledge to deep-sea ecosystems so that we can better understand their functioning.




Drazen JC, Bird LB, Barry JP (2005) Development of a hyperbaric trap-respirometer for the capture and maintenance

      of live deep-sea organisms. Limnology and Oceanography: Methods 3: 488-498

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Last updated 02/14/14

Drazen JC (2008) Energetics of grenadier fishes. In: Orlov AM, Iwamoto T (eds) Grenadiers of the World Oceans: Biology, Stock assessment, and Fisheries. American Fisheries Society, pp 203-223 pdf


Seibel BA, Drazen JC (2007) The rate of metabolism in marine animals: environmental constraints,  ecological demands and energetic opportunities. Philosophical Transactions of the Royal Society of London, B 362: 2061-2078  pdf


Drazen JC, Seibel BA (2007) Depth-related trends in metabolism of benthic and benthopelagic deep- sea fishes. Limnology and Oceanography 52: 2306-2316  pdf


Drazen JC, Reisenbichler KR, Robison BH (2007) A comparison of absorption and assimilation efficiencies between four species of shallow- and deep-living fishes. Marine Biology 151: 1551-1558  pdf


Drazen JC (2007) Depth related trends in proximate composition of demersal fishes in the eastern North Pacific. Deep Sea Research I 54: 203-219  pdf


Drazen JC, Bird LB, Barry JP (2005) Development of a hyperbaric trap-respirometer for the capture and maintenance of live deep-sea organisms. Limnology and Oceanography: Methods 3: 488-498 pdf


Gutowska MA, Drazen JC, Robison BH (2004) Digestive chitinolytic activity in marine fishes of Monterey Bay, California. Comparative Biochemistry and Physiology A 139: 351-358  pdf


Drazen JC (2002) Energy budgets and feeding rates of Coryphaenoides acrolepis and C. armatus. Marine Biology 140: 677-686   pdf