Monday, December 20, 2010

Chesapeake crab recovery highlighted in Science article

The recovery of female crabs in the Chesapeake Bay that has occurred since female harvest was restricted in 2008 is the focus of a recent Science magazine article. I've copied the summary below, but you need a subscription to view the entire article.

Science 10 December 2010: Vol. 330 no. 6010 p. 1474 DOI:
10.1126/science.330.6010.1474
News Focus Fisheries
Fisheries
Chesapeake Crabs: Engineering a Rebound
Christopher
Pala
*

Summary

By stopping harvesting early in Chesapeake Bay, when the fall female
migration is at its peak, one of the world's largest crab fisheries was brought
from the brink of collapse to a healthy population in just 3 years. A winter
dredge of buried hibernating pregnant females in Virginia—which killed two
females for every one caught—was also closed. Those fishers were hired with
federal funds to recover lost traps, which continue to kill scores of crabs.
Finally, a spawning-season sanctuary was extended. As a result, the spring 2009
survey of 1500 spots up and down the bay found that the female population had
climbed by 70%, while the male population barely changed. This spring, the
survey showed that the number of females was up 200% over the 2008 figure.
Overall, the number of crabs has soared from 131 million in 2008 to 315 million
this year.

Sunday, October 3, 2010

Proposed crab rule changes in Florida

There are some proposed rule changes to for crabbing in Florida.

See this from Tampa Bay Online:

FWC proposes changes to blue crab rules

LAKELAND - The Florida Fish and
Wildlife Conservation Commission (FWC) proposed a series of draft rule
amendments to modify blue crab regulations. These proposals include some
recommendations by the FWC's Blue Crab Advisory Board, which helps the
Commission manage Florida's blue crab fishery, as well as some technical blue
crab amendments.

One proposed rule amendment by the board would change the
six annual regional, 10-day blue crab trap closures to occur every other year.
The January closure to the harvest of blue crabs with traps in the St. Johns
River system and the August closures in Nassau through Palm Beach counties would
occur in even-numbered calendar years only. The July closures in Broward through
Wakulla counties and the January closure in Franklin through Escambia counties
would occur in odd-numbered calendar years only. This proposed change would help
focus trap cleanup efforts in each region and lessen the economic impact of the
closures on individual crabbers.

Other board-proposed rule amendments would
change the blue crab license-endorsement transfer window from September through
December to May through February to increase opportunities for crabbers to
transfer their endorsements to someone else and allow initial blue crab trap
tags to be ordered at any time.

The FWC also is proposing technical rule
amendments that would allow qualified blue crab harvesters to designate another
of their own vessels to be used to temporarily pull blue crab traps while their
regular vessel is repaired or replaced and clarify that soft shell blue crab
harvesters may hold only two soft shell endorsements at one time.

The FWC
will hold a final public hearing on these blue crab draft rule proposals at its
December meeting in Weston. More information regarding the proposed draft rules
is available online at MyFWC.com/Commission, linked from the Sept. 1-3 meeting
agenda.

Mixed news on crab supplies

Seafood dealers and restaurants have had trouble stocking live blue crabs this summer in the Chesapeake Bay area, but not because of new problems in the Bay. Louisiana has become a major supplier of blue crabs, but the Deepwater Horizon oil spill interrupted that supply this summer, as this article on nola.com details.

It's a different story in Florida, where crab harvests are good after a rainy spring and summer. I find it a bit odd that every article I've found about the blue crab harvest in Florida includes instructions on how to cook them, but you might as well create a market for all the crabs that are caught to keep prices up.

Monday, September 27, 2010

In search of young of the year


One of the projects I'm working on this year is an attempt to study disease in blue crabs during early life history. It is part of a collaboration with Dr. Eric Schott and his students at the University of Maryland Institute of Marine and Environmental Technology.

Blue crab larvae spend their first month or so in the ocean, then migrate into estuaries where they grow as juveniles and mature into adults. Our team has been out a couple of times a month since April searching for young of the year crabs. Juveniles have been relatively easy to catch, hiding in the shallows at the edge of tidal creeks during low tide. "Easy" is a relative term here in the Georgia salt marshes as you can see from the photo.
Megalopae (the larval stage that migrates from the ocean to the estuary) have been harder to come by. After many unsuccessful nights of plankton sampling over the summer, I've finally been catching a few each night that I've been out over the last month. There are far fewer here than where I did my Ph.D. work in Beaufort, NC. In NC we could have caught the several hundred we need for this study in a single night.

Thursday, August 26, 2010

Black gill crabs turn up in Mississippi - Oil not a likely cause



Crabs with black gills recently turned up in Mississippi (wlox story). Local fishermen say they have never seen anything like it, but are worried these crabs are stained with oil. Black gills in crabs can be associated with disease ("black gill syndrome"), low oxygen levels, high levels of detritus, and pollution or a combination of the above.


Testing has so far indicated that oil is not involved, but that low oxygen levels and detritus are more likely causes (oilspillaction.com).



“The FDA has advised that, following extensive sensory testing and chemical
analysis, tissue samples tested indicate that crabs from these previously closed
areas south of the barrier islands are safe for consumption,” stated a news
release from DMR and DEQ. “Testing for crab tissues includes specimens of
special interest, such as those with dark gills, brought to DMR’s attention by
concerned fishermen and the public; all of these samples have been determined to
be safe for consumption as well.”

Jewell said no exact cause has been determined for the dark gills found
on some crabs, but low dissolved oxygen levels and sediment are suspected.

“A lot of the low dissolved oxygen in our waters is because we have
very high temperatures,” he said. “That can be part of the issue, but I don’t
think it is any one thing.”

The crabs with dark gills that been brought to DMR by the public have
come from upper bay areas, he said. “There is a lot of sediment and a lot of
suspended sediment and that tends to get entrapped on the crabs’ gills,
particularly crabs that are stressed.”

The darkening is not found on any other crab organs, he said, “which
tends to indicate it has to do with respiration.”

Crab samples tested, including the dark gills, have returned as free of
oil or trace amounts in the parts per trillion range were found, he said.

“Anything they are finding is way below the NOAA protocol,” he
said.

Sunday, August 1, 2010

New key for blue crab megalopae and juveniles


Adult blue crabs are distinctive. Olive shell set off with blue legs and claws and an undeniable fighting spirit. Young larvae and juveniles, however, are very difficult to distinguish from some of their close cousins. I had great news last week that a manuscript I have been working on since 2005 was accepted to the Journal of Crustacean Biology and is due out in early 2011. When I first started studying blue crabs in 2004, I was faced with the challenge of separating blue crab (Callinectes sapidus) megalopae from those of the lesser blue crab (Callinectes similis). I couldn’t make heads or tails of the problem because the original descriptions of the megalopae didn’t seem to match what I was collecting in the wild. A colleague was kind enough to pass along an unpublished manuscript by Ken Stuck and others that made separation of the species possible, if still not exactly easy at first. After contacting the authors of the original publication for permission, I combined data from the original manuscript with new data that I collected, and submitted the new manuscript. It includes drawings of both blue crab and lesser blue crab megalopae and juveniles and keys for separating them from similar species occurring along the US Atlantic and Gulf coasts. If a copy of the manuscript would be useful for your work, please contact me and I’ll send one your way.


Have new blue crab research your are publishing? Send a description and I'll include it in the blog.

Wednesday, July 21, 2010

Prospects for the next generation

It's the time of year when crab spawning is at its peak. Prospects for the next generation, the new year-class of baby crabs due in the fishery in 2012, are very mixed. Newly hatched zoea larvae face an uncertain future in the Gulf. The Deepwater Horizon oil spill and the dispersants used on it will have an unknown effect on the environmentally sensitive young larvae that spend their first month or so of life floating around in coastal waters. If they survive their time in the Gulf, they will migrate to salt marshes and seagrass beds that may also be contaminated. What this means for the future of the Gulf crab fishery is largely unknown.

Along parts of the Atlantic coast, things are looking better for crabs and crabbers than they have in over a decade. Restrictions on fishing in the Chesapeake Bay have led to high numbers of spawning females and, for the first time this spring, a significant increase in the number of juveniles. Some of the increase in reproduction could spill over into adjacent states, especially the Albemarle-Pamlico sound region of North Carolina.

Here's to hoping the new generation is a good one.

Friday, June 18, 2010

Tough crabbing in the Gulf

Coming only a few years after Hurricane Katrina, the Deepwater Horizon oil spill threatens the livelihoods of fishermen along much of the Gulf Coast. Here's a report from Tino Mones Seafood in Delacroix Island, LA (USA Today).

The low harvest in LA is causing the price of fresh crabs to rise (WHYY - Philadelphia).

Saturday, May 1, 2010

Chesapeake Bay crab numbers up

Good news for crabs in the Chesapeake Bay as the 2010 winter dredge survey showed significant increases in both adult and young of the year crabs (Maryland DNR). Dr. Rom Lipcius of the Virginia Institute of Marine Science was quoted as saying:

“The substantial rise in abundance of mature crabs and juveniles was clearly a response of the crab population to unprecedented management actions, such as the closure of the winter dredge fishery, by the Virginia Marine Resources Commission and partner agencies. The increase was neither a random event nor a reflection of improved environmental conditions,” said Dr. Rom Lipcius who directs the VIMS component of the dredge survey.

View figures from the dredge survey report here.

Sunday, March 21, 2010

Virginia crab harvest opens for first time after license buybacks

The Chesapeake Bay blue crab fishery has endured substantial change since a federal fishery failure was declared in September 2008 (Chesapeake Bay Program). Efforts to reduce fishing pressure have included a 30% reduction in fishing pots that may have helped increase the number of crabs collected in the 2009 winter dredge survey, although 2010 survey results have not yet been released (WTOP).

The 2010 fishing season opened in VA last week for the first time since the latest effort reduction strategy, a license buyback program, was conducted last fall. Declaration of a federal fishery failure made federal funds available to support the declining fishery. Both Maryland and Virginia received funds to buy licenses back from fishermen in an attempt to reduce the level of fishing. Virginia successfully bought back 359 commercial fishing licenses, reducing its total number of pots by 75,000 (Chesapeake Bay Program). Maryland, however, deemed the bids it received for its limited commercial crabber licenses to be too high and cancelled the program (Washington Post).

Time will tell whether the effort-reduction programs succeed in returning the Bay crab fishery to sustainable levels. Let's hope the 2010 winter dredge survey show continued increases in spawning stock.

Saturday, January 30, 2010

Stock Assessments and Management Plans

How are blue crab fisheries managed? What biological, economic and social factors are taken into account? How do fishery managers determine how many crabs are out there to be caught?

The answers vary greatly from state to state. State fishery management plans can be hard to find online. I've started putting together links to blue crab stock assessments and fishery management plans on my website. I'm working on finding links to management plans for each state in which blue crabs are caught commercially, but some are either difficult to find or are not available on the web. Pat Geer of the Coastal Resources Division of Georgia Department of Natural Resources was very helpful in responding quickly to a request to post the Georgia blue crab management plan.

If you find links to other state or regional plans, send them my way and I'll add a link.


Thursday, January 7, 2010

Death of a Legend

Willard Van Engel, legendary Chesapeake Bay blue crab researcher, passed on Dec. 25, 2009 at the age of 94.

From the Daily Press in Newport News, VA (link):

"HAYES - Dr. Willard A. Van Engel (known as "Van"), professor emeritus with the Virginia Institute of Marine Science, died Dec. 25, 2009, at the age of 94.A native of Milwaukee, Wis., Dr. Van Engel received his bachelor and master degrees in the late 1930s from the University of Wisconsin-Madison. Van was stationed in Europe, where he served as a meteorologist in the U.S. Army Air Force during World War II. In 1946, he moved to Yorktown and became affiliated with VIMS (which was then named the Virginia Fisheries Laboratory), where he developed an interest in blue crab research.

At a time when calculations were done with slide rules and adding machines, Van and his colleagues were on the cutting edge of research in the Chesapeake Bay. Van's early papers on the blue crab fishery formed the fundamental nucleus of work in the field. He and his colleagues at the Virginia Fisheries Laboratory, in the late 40s, had the great foresight to create what has grown to be the diverse academic community of VIMS today. In 1947, Van accurately predicted the need for keeping duplicates and reprints of scientific papers and reports in a centralized location, thus, Van became the founder of the VIMS Library. At the American Association for the Advancement of Science meeting in 1948, Van and others, who at the time called themselves the "Brackish Boys," created what later became known as the Atlantic Estuarine Research Society, of which Van was the first Secretary-Treasurer. William W. Warner, the author of Beautiful Swimmers, called Van "the complete estuaries biologist, as much at home in theoretical discussions with his scientist colleagues as he is in meeting with watermen throughout the Bay . . . ."

Besides his key relationships with the Virginia Marine Resources Commission, industry, and watermen, Van also foresaw the need for a fisheries survey for the blue crab, which has become the longest ongoing data set for the blue crab, or any other Portunid (swimming) crab worldwide. Van's varied research interests included many areas we take for granted today such as the relationship between recruitment dynamics and environmental parameters. When Van retired from VIMS in 1985, at the age of 70, he was the longest serving employee at almost 39 years. A year later, Van created a fellowship to support graduate student research on crustaceans.

In recent years, he received two significant recognitions. In 2003, VIMS presented Dr. Van Engel its first Lifetime Achievement Award for outstanding academic and scientific research contributions and continued support to VIMS, and in 2006, the College of William and Mary presented him an honorary doctorate of science. After retirement, he enjoyed riding his horses, sharing with his friends and being an active member of the Gloucester Point Rotary Club.

He was preceded in death by his parents, Maurice and Frieda Aaron Van Engel; and brothers, Earl L., and Maurice B. Van Engel.

The Van Engel Fellowship Board would like to extend sincere appreciation and thanks to Jerry and Anne Edwards for their friendship, love and care they contributed to the life and times of this wonderful man. At his request, services will be private and to continue the legacy he established for students, memorial contributions may be made to The Willard A. Van Engel Fellowship, Inc., VIMS, c/o Robert Harris Jr., Treasurer, P. O. Box 1346, Gloucester Point, VA 23062-1346. "