Nav: Home

Fish shrinking as ocean temperatures rise

October 04, 2017

One of the most economically important fish is shrinking in body weight, length and overall physical size as ocean temperatures rise, according to new research by LSU Boyd Professor R. Eugene Turner published today. The average body size of Menhaden -- a small, silver fish -- caught off the coasts from Maine to Texas -- has shrunk by about 15 percent over the past 65 years.

Menhaden make up about one-half of the Atlantic and Gulf of Mexico fish harvest and had a dockside value of about $129 million in 2013. They are coastal species that spawn offshore and move to estuaries where juveniles grow to one- and two-year old fish. The air and sea surface temperature off the Atlantic coast and the Gulf of Mexico has steadily increased, especially in estuaries, where heat exchange occurs efficiently between air and sea. Adult menhaden return offshore where they are harvested with purse seine nets.

Menhaden are a significant food source for birds, seals, whales, striped bass and other animals. Therefore, the consequences of Menhaden shrinking in body size extend throughout the food web.

Turner calculated the weight and length changes of these fish using data collected by the National Marine Fisheries Service. From 1955 to 2008, about 495,000 Atlantic menhaden were collected by the agency. From 1964 to 2010, about 510,000 Gulf of Mexico menhaden were collected. The data shows a decline in annual weight and length among 3-, 4- and 5-year-old fish. For example, a 4-year-old fish captured in 2010 weighed 11 percent less than a 4-year-old fish captured in 1987.

"These changes are closely related to variations in the annual air temperature, which we used as a proxy for water temperature, for fish on both coasts," Turner said. "As the Earth's atmosphere and oceans continue to warm, the future of menhaden, it seems, will be even smaller."
-end-


Louisiana State University

Related Body Weight Articles:

Brain receptor that regulates body heat may also help accelerate weight loss
The brain mechanism that enables us to maintain a constant body temperature may also be the key to rapid weight loss, a new study finds.
Short-term study suggests vegan diet can boost gut microbes related to body weight, body composition and blood sugar control
New research presented at this year's Annual Meeting of the European Association for the Study of Diabetes (EASD) in Barcelona, Spain (Sept.
Increased body weight in adolescent boys linked with heart attack before 65
A study in nearly 1.7 million 18-year-old boys has found that higher body mass index (BMI) is linked with greater risk of a heart attack before 65 years of age.
Substantial increase in body weight since 1960s due to interplay between genes and environment
People with a genetic predisposition to obesity are not only at greater risk of excess weight, their genes interact with an increasingly 'obesogenic' environment, resulting in higher body mass index (BMI) in recent decades, finds a study from Norway published by The BMJ today.
Excess weight and body fat cause cardiovascular disease
In the first Mendelian randomization study to look at this, researchers have found evidence that excess weight and body fat cause a range of heart and blood vessel diseases (rather than just being associated with it).
New brain mechanisms regulating body weight
Researchers at University of Gothenburg, Sweden, clarify the link between the molecule interleukine-6 (IL-6) in the brain and obesity.
Excess body weight before 50 is associated with higher risk of dying from pancreatic cancer
Excess weight before age 50 may be more strongly associated with pancreatic cancer mortality risk than excess weight at older ages, according to results of a study presented at the AACR Annual Meeting 2019, March 29-April 3.
Personality type could shape attitudes toward body weight of others, researchers say
Researchers found that personality traits have significant bearing on a person's attitudes toward obesity, their implicit theories of weight and their willingness to engage in derisive fat talk or weight discrimination.
Proportion of cancers associated with excess body weight varies considerably by state
A new study finds an at least 1.5-fold difference in the share of cancers related to obesity between states with the highest and lowest proportions.
Excess body weight responsible for nearly 4 percent of cancers worldwide
Excess body weight accounted for approximately 3.9 percent of all cancers worldwide in 2012, a figure that is expected to rise in the coming decades given current trends.
More Body Weight News and Body Weight Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#543 Give a Nerd a Gift
Yup, you guessed it... it's Science for the People's annual holiday episode that helps you figure out what sciency books and gifts to get that special nerd on your list. Or maybe you're looking to build up your reading list for the holiday break and a geeky Christmas sweater to wear to an upcoming party. Returning are pop-science power-readers John Dupuis and Joanne Manaster to dish on the best science books they read this past year. And Rachelle Saunders and Bethany Brookshire squee in delight over some truly delightful science-themed non-book objects for those whose bookshelves are already full. Since...
Now Playing: Radiolab

An Announcement from Radiolab