VANCOUVER, Oct. 31 (Xinhua) -- Putting research instruments such as satellite tags on aquatic animals can help scientists better understand the animals' behavior, but it could also disrupt their natural behavior, according to a new study published Thursday.
In the study, carried in the Methods in Ecology and Evolution journal, Canadian and American researchers have for the first time quantified the energy cost to aquatic animals when they carry satellite tags, video cameras and other research instruments.
In order to study the ecological impact of animal-borne instruments on aquatic animals, the researchers made fiberglass casts of sea turtles and put them in a wind tunnel.
They found that while most commercially available tags increased drag by less than five percent for large adult animals in the wild, these same devices increased drag by more than 100 percent on smaller or juvenile animals.
"Many marine animals make yearlong breeding migrations crossing entire oceans, while others may rely on high speeds and acceleration -- enabling them to catch prey or to escape predators," said T. Todd Jones, who led the study as a doctoral fellow at Canada's University of British Columbia.
"If the drag costs from carrying tags disrupt their natural behavior, they may miss out on breeding and foraging seasons, be unable to catch enough food, or even end up becoming someone else's meal."
The study also includes a universal formula that allows scientists to calculate drag for a wide range of marine species including turtles, mammals, fish, and diving birds to inform study design.
Jones said that excessive drag may also impede the collection of research data in the wild, and the guidelines they have developed can help ensure that the data collected accurately reflect the animals' natural behavior in the wild.