Small fish recover faster than large fish

Sep 21, 2011
This is a largemouth bass being released. Credit: University of Illinois

In football, linebackers are usually the largest players and have the endurance required to get through a game plus overtime. But when it comes to fish, larger doesn't always mean stronger. A University of Illinois study showed smaller fish recover from exertion faster than larger fish.

"The point of the study was to replicate an angling situation where anglers catch and release fish," said researcher Cory Suski. "We wanted to know if large fish and small fish had similar to being exercised and released, particularly regarding the time it takes the fish to recover from exercise.

"What we found is that the large fish take longer to recover from exercise than the small fish do. None of the fish really experienced any major , and they all survived easily, but the small fish recovered faster than the big fish."

Suski said the findings will be important for conservation.

"Big fish are reproductively valuable as they tend to have more babies than small fish," he said. " Big fish are also rarer than small fish, and they are more often targeted by anglers. If anglers are planning to release a large fish after catching it, the results from this study emphasize the importance of angling the fish for a short duration, handling the fish gently, and getting it back into the water quickly so that excessive disturbances are minimized and the fish can recover quickly, begin feeding, and get back to normal."

The fish in the study were largemouth bass. They were caught in nets, put into dark tanks and allowed to rest.

Later they were chased for 60 seconds to simulate angling and the amount of energy they might expend during a catch-and-release episode. They were allowed to recover for 0, 1, 2, or 4 hours before being sampled for plasma and white muscle.

Large largemouth bass exhibited elevated concentrations of and relative to small fish following the exercise challenge.

Large fish required additional time to clear metabolic disturbances in plasma and failed to restore potassium to basal levels even following 4 hours of recovery, indicating an improved ability of the smaller fish to recover from disturbances.

"Before we began the research, we predicted that the larger fish would respond and recover from exercise more quickly, providing another size-based advantage for larger fish, but we found the opposite to be true," Suski said.

Suski said anglers have always known that big fish are special, and the results of this study emphasize the need to treat big fish gently so they can be caught again in the future.

The effect of body size on post-exercise physiology in largemouth bass was published in Physiology and Biochemistry. Andrew J. Gingerich co-authored the paper.

Explore further: Ivory mafia: how criminal gangs are killing Africa's elephants

add to favorites email to friend print save as pdf

Related Stories

Research cautions to catch-and-release in less than 4 minutes

Sep 27, 2007

Recreational fishing that involves catch-and-release may seem like just good fun, and that released fish go on to live happily ever after, but a recent study at the University of Illinois shows that improper handling techniques ...

How to Grow a Bigger Brain

Mar 06, 2006

Hatchery-reared steelhead trout show increased growth of some parts of the brain when small stones are scattered on the bottom of their tank, according to a new study by researchers at UC Davis. The brains ...

Intensive fishing leads to smaller fish

May 07, 2010

(PhysOrg.com) -- Intensive fishery activities in the North Sea have resulted in evolutionary changes in fish. Fish remain smaller, grow slower and mature sexually earlier. This is postulated by Fabian Mollet, fishery researcher ...

Over-fishing: Fewer eggs, smaller fish

Jan 19, 2006

A University of California-Riverside study suggests harvesting the largest individuals from a fish population introduces harmful genetic changes.

Recommended for you

The elephant poaching business in numbers

5 hours ago

From the pittance paid to local poachers to a multi-billion dollar industry, here are some of the key numbers related to Africa's endangered elephants:

Kalbarri abalone gets helping hand

Jan 23, 2015

Department of Fisheries staff and Kalbarri fishermen have released 24,000 Roe's abalone (Haliotis roei) onto reef platforms along the cliffs north of Kalbarri, to restock a population decimated by the marine ...

Cichlid sisters swim together in order to reach the goal

Jan 23, 2015

The manner and routes of dispersal vary with the species and the ecological conditions. Many fish form shoals to avoid predation. Shoaling with familiar conspecifics affords the fish an even greater advantage ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.