Bonefish study

Several factors suggested for bonefish decline

 

A study contended that many possibilities might share the blame for the decline of a sport fish that is vital to the Florida Keys economy.

scocking@MiamiHerald.com

A decline in prey like shrimp and crabs is not the main cause of the drop in bonefish populations in Florida Bay, according to a one-year study conducted by Audubon Florida and funded by the nonprofit Bonefish Tarpon Trust.

The study by researchers Pete Frezza, Shawn Liston, Jerry Lorenz and Michelle Robinson suggests other factors — the diversion and quality of freshwater delivered to Florida Bay; toxins in bottom sediments; pollutants from farms and yards; increased boating pressure; mercury contamination; and ocean acidification — might share the blame for the decline of a sport fish that pumps $427 million annually into the Florida Keys economy.

“While a decrease in prey may likely have been part of the cause of the decline since the 1980s [and perhaps even earlier], prey abundance alone does not appear to explain the dramatic decline in Florida Bay bonefish that has occurred in recent years [since 2006],” the authors wrote.

Protected areas

The researchers recommend implementing marine-protected areas for bonefish such as pole/troll and catch-and-release-only zones in Everglades National Park and the Florida Keys National Marine Sanctuary. They endorse Everglades restoration initiatives, such as bridging the Tamiami Trail and completing the second phase of the C-111 project to improve the quality and quantity of freshwater flowing into Florida Bay.

The study — conducted in 2012 — compared flats in the Lower Keys, Upper Keys and Biscayne Bay to see if creatures bonefish eat — such as blue crabs, pink shrimp, toadfish and others — were less abundant than in the 1980s and ’90s when initial research by other scientists was conducted. The Audubon researchers measured sea grass cover and collected prey at each site.

They found that Sawyer Key in the Lower Keys had more prey and more bonefish while the Upper Keys had fewer prey and fewer bones. But when they compared the numbers with those from the earlier studies, they found no real decline in prey at those sites.

“It certainly wasn’t a smoking gun,” Aaron Adams, operations director at Bonefish Tarpon Trust, said. “I guess I was a little bit surprised at the lack of difference between the current prey abundance and in the 1980s and ’90s. It just means we have to step back and look at other possibilities.”

Further research

Adams said the Trust is looking into conducting further research, such as “what if there’s something in the water that’s interfering with bonefish’s ability to reproduce.” He suggested examining bottom sediments for contaminants and sampling the fish themselves to see if they are absorbing harmful toxins. Future projects might include trying to raise bonefish in captivity then restocking them.

“Once we can figure out the causes, we can begin work on restoring the bonefish population,” he said.

Read more Outdoors stories from the Miami Herald

  •  
Boaters and divers look for lobster off Cape Florida on Wednesday July 30, 2014.

    LOBSTER MINISEASON

    Ex-Penn football player dies on dive during lobster miniseason

    A Broward man lost his life diving on the first day of the lobster miniseason. He might have run out of air.

  • Fishing report

    Captain Gil Gutierrez of Lucky Fishing Charters out of TNT Marina in Keystone reported that nighttime snapper fishing on the reefs offshore of Miami has been red hot. Plenty of mangrove, mutton and yellowtail snappers are biting cut bait over the reef in depths of 25 to 60 feet of water. Captain Bill Hauck from the party boat Sea King out of Marathon reported the nighttime mangrove snapper fishing on the reef is off the chart. Nighttime snapper anglers are having no problem catching a limit of snappers, which are eating ballyhoo and threadfin herring.

  • Outdoors notebook

    Off-road vehicles such as swamp buggies, street-legal 4x4s, ATVs and UTVs will be allowed back in the Big Cypress National Preserve on Friday, marking the end of the annual 60-day recreational closure to ORV access. Only the designated primary trails in the backcountry will be open. All secondary trails will remain closed for an additional 60 days. The closure does not affect landowners’ access to private property using permitted trails. For more information, visit www.nps.gov/bicy.

Miami Herald

Join the
Discussion

The Miami Herald is pleased to provide this opportunity to share information, experiences and observations about what's in the news. Some of the comments may be reprinted elsewhere on the site or in the newspaper. We encourage lively, open debate on the issues of the day, and ask that you refrain from profanity, hate speech, personal comments and remarks that are off point. Thank you for taking the time to offer your thoughts.

The Miami Herald uses Facebook's commenting system. You need to log in with a Facebook account in order to comment. If you have questions about commenting with your Facebook account, click here.

Have a news tip? You can send it anonymously. Click here to send us your tip - or - consider joining the Public Insight Network and become a source for The Miami Herald and el Nuevo Herald.

Hide Comments

This affects comments on all stories.

Cancel OK

  • Marketplace

Today's Circulars

  • Quick Job Search

Enter Keyword(s) Enter City Select a State Select a Category