Wednesday, March 02, 2005

Do Fish Feel Pain? (And, if so, what of it?)



"Fish do feel pain, scientists say" was published by the BBC in April 2003. More involved research on the subject of pain perception in fish has been carried out since 2003, but the BBC article was forwarded to me only yesterday. Two years after publication, the story is making blog and email rounds.

Frankly, I'm not sure why the subject is still generating debate. Fish do feel pain; this is the scientific consensus.

A more complex question, however, is how the fish interpret the sensation of pain. In animals with a more highly developed brain - mammals and birds - pain describes a local problem, prompting the animal to act with this information in mind. For example, if you fall and break your leg, you experience terrible pain where the bone is broken, thus alerting you to the serious nature of the injury.

Fish, reptiles and amphibians possess only a simple brain, similar in construction and function to the human brain stem. Researchers question if pain serves any function in these more basic brains. Because mammalian fear and flight-or-fight reactions have been shown to originate in the amygdala, an organ of the limbic system, and because fish, reptiles and amphibians lack a limbic system, I assume that they understand pain only as an immediate sensation (and do not experience pain-related stress as mammals do).

Living in New York City, I no longer get to do much fishing. Happily, this past summer I traveled to Alaska and caught several large Pacific halibut (Hippoglossus stenolepis) and both silver (Oncorhynchus kisutch) and pink salmon (Oncorhynchus gorbuscha). I eagerly consumed these fish, but I wonder about the stress (if any) that game fish are put through in the process of being caught.

Depending on what scientists determine, catch-and-release fishing, long considered an eco-friendly option, may be deemed controversial by both biologists and animal rights groups in the coming years.

Photo credit: Hungry Hyaena, 2001

No comments: