A 22-pound, 5-ounce largemouth bass (picture) has been caught by Manabu Kurita, a pro staffer representing Deps Tackle Co. in Japan. This breaks George Perry’s old record from June 2, 1932. The bass caught by Perry in Montgomery Lake, Georgia 77 years ago weighed 22-pound, 4-ounce – just a tad less than the new Japanese record bass. Kurita’s bass was 29.4 inches long (no girth measurements have been released). It was reportedly weighed on a certified scale.

Kurita caught his 22-pound, 5-ounce bass in Lake Biwa (琵琶湖, Biwa-ko), in Japan’s Shiga Prefecture. Formed by tectonic shifts almost 4 million years ago, Lake Biwa is one of the world’s twenty oldest lakes and home to a very rich ecosystem that includes 58 described endemic species. It is the largest freshwater lake in the country and covers nearly 259 square miles.

After holding the International Game Fish Association (IGFA) all-tackle world record for 77 year, it seems as if Perry might have to if not step down then at least share the first place with his fellow Japanese angler. IGFA rules stipulate that a bass must weigh two ounces more than the current record holder to break the record, so Kurita’s fish will only tie it.

“It will tie [Perry’s record] if that’s the weight,” says Jason Schratwieser, record andconservation director for the game fish association. “For record fish weighing less than 25 pounds, the replacement record must weigh at least 2 ounces more than the existing record.”

In 2006, Mac Weakley caught a 25-pound, 1-ounce bass in Lake

Dixon, California, but he didn’t pursue the record since he accidently foul-hooked the fish, i.e. he didn’t hook the fish in the mouth.

The inclination to end up stuck on a hook seems to be a heritable trait in bass, according to a study published in a recent issue of the Transactions of the American Fisheries Society.

The study, which was carried out by researchers DP Philipp, SJ Cooke, JE Claussen, JB Koppelman, CD Suski, and DP Burkett, focused on Ridge Lake, an Illinois lake where catch-and-release fishing has been enforced and strictly regulated for decades. Each caught fish has been measured, tagged and then released back into the wild.

Picture by: Clinton & Charles Robertson from Del Rio, Texas & San Marcos, TX, USA

David Philipp and coauthors commenced their study in 1977, checking the prevalence of Largemouth bass (Micropterus salmoides) on the hooks of fishermen. After four years, the experimental lake was drained and 1,785 fish were collected. When checking the tags, Philipp and his team found that roughly 15 percent of the Largemouth bass population consisted of specimens that had never been caught. They also found out that certain other bass specimens had been caught over and over again.

To take the study one step further, the research team collected never caught bass specimens (so called Low Vulnerability, LV, specimens) and raised a line of LV offspring in separate brood ponds. Likewise, the team collected bass specimens caught at least four times (High Vulnerability, HV, specimens) and placed them in their own brooding ponds to create a HV line.

The first generation (F1) offspring from both lines where then marked and placed together in the same pond. During the summer season, anglers where allowed to visit the pond and practise catch-and-release, and records where kept of the number of times each fish was caught.

As the summer came to an end, HV fish caught three or more times where used to create a new line of HV offspring, while LV fish caught no more than once became the parents of a new LV line.

The second generation (F2) offspring went through the same procedure as their parents; they were market, released into the same pond, and subjected to anglers throughout the summer. In fall, scientists gathered the fish that had been caught at least three times or no more than once and placed them in separate ponds to create a third generation (F3) HV and LV fish.

A following series of controlled fishing experiments eventually showed that the vulnerability to angling of the HV line was greater than that of the LV line, and that the differences observed between the two lines increased across later generations.

If this is true not only for bass but for other fish species as well, heavy hook-and-line angling pressure in lakes and rivers may cause evolutionary changes in the fish populations found in such lakes. Hence, a lake visited by a lot of anglers each year may eventually develop fish populations highly suspicious of the fishermen’s lure.

More information can be found in the paper published in Transactions of the American Fisheries Society: Philipp, DP, SJ Cooke, JE Claussen, JB Koppelman, CD Suski and

DP Burkett (2009) Selection for vulnerability to angling in Largemouth Bass. Transactions of the American Fisheries Society 138, pp. 189–199.

A recent study on intersex abnormalities in fish living in the Potomac River watershed carried out by researchers from the U.S. Fish and Wildlife Service and the U.S. Geological Survey showed that at least 82 percent of male smallmouth bass and in 23 percent of the largemouth bass had immature female germ cells (oocytes) in their reproductive organs. This number is even larger than anticipated.

This type of intersex indicates that the fish has been exposed to estrogens or chemicals that mimic the activity of natural hormones. The condition is believed to be caused by hormone-like chemicals, so called endocrine disruptors, found in medicines and a variety of consumer products. Earlier, researchers suspected that the contaminants were entering the Potomac from the wastewater treatment plants that discharge into it, but further sampling showed that the problem existed in areas located upstream from sewage plants as well. Officials are now investigating if multiple chemicals, and not just those from sewage plants, may be responsible. A larger study that includes the entire Potomac River and other East Coast rivers will be launched to find out how widespread the problem actually is.

“At the moment we don’t know the ecological implications of this condition and it could potentially affect the reproductive capability of important sport fish species in the watershed,” said Leopoldo Miranda, Supervisor of the U.S. Fish and Wildlife Service’s Chesapeake Bay Field Office.

The Potomac River is the fourth largest river along the Atlantic coast of the USA (in terms of area), with a length of approximately 665 km (383 statute miles) and a drainage area of roughly 38,000 km² (14,700 square miles). It flows into the Chesapeake Bay along the mid-Atlantic coast of the U.S. The river is shared by West Virginia, Maryland, Virginia, and District of Columbia, and all of Washington, D.C., the nation’s capital city, lies within the Potomac watershed.

More information is available in the Intersex fact sheet released by the U.S. Fish and Wildlife Service’s Chesapeake Bay Field Office.

During the last week of August, Gary Owen, a Charles County sheriff’s corporal, discovered 167 snakeheads swimming in two puddles off Sharpersville Road near Mattawoman Creek in Maryland. Mattawoman Creek is a tidal tributary of the Potomac River located in Prince George’s and Charles Counties. The sheriff’s corporal was not actually on the look-out for invasive species when he did his unexpected discovery; he was leading a news crew to a location where a homicide victim was found almost 30 years ago.

The group of 167 snakeheads, who inhabited two puddles under a tree stump, consisted of two adult fish and 165 youngsters. The two adults were a male and a pregnant female. When the finding was reported to the Maryland Department of Natural Resources, they decided to kill all fishes and take them to their laboratory for further examination.

Mattawoman Creek is considered one of the best creeks for bass fishing on the East Coasts and anglers now worry that snakeheads might cause injury to the bass populations by competing for the same prey or by preying on smaller bass.

Snakeheads are not a natural part of the Maryland fauna; they hail from Africa and South East Asia, and conversationalists fear that these skilled predators could disrupt native ecosystems if there were allowed to establish themselves in the U.S. Snakeheads became the centre of quite a media frenzy when they were discovered in Maryland in 2002 as the first known examples of a breeding population of wild snakeheads in the U.S. You can read more about it in our article “Environmental effects of Snakeheads”. You can see how widespread sakeheads have become in parts of the Potomac river in this video.

Since 2003, it is illegal to import snakeheads to the United States.

A video about the snakehead situation in the Potomac river. In certain areas of the river snakeheads now are established and competing with local fish species such as local bass. Hopefully they will be kept confined to certain parts of the river and won´t spread to other parts of the country. We will just have to wait and see. in the meen time the snakehead is turning into a popular game fish luring sport fishers to the area. For more info see the almost 3 min long video.

Releasing caught snakeheads are illegal and catches should be reported to the local fish and wildlife service.

The Black Sea Bass is a popular fish among sport fishers and sushi lovers alike, but during recent decades the landings have decrease along the United States Atlantic coast. This has caused the National Oceanic and Atmospheric Administration (NOAA), a governmental agency responsible for supervising National Marine Sanctuaries, to launch two separate culture trials focused on Black Sea Bass farming in aquacultures. So far, the results have been promising, according to an article published by Physorg.com.

Fishery biologists at the NOAA National Marine Fisheries Service lab in Milford, Connecticut, have been able to show that Black Sea Bass can be spawned in captivity and grown from larvae to adults in a so called recirculation aquaculture system (RAS). The Black Sea Bass is a hermaphrodite. It starts out as a female and will then turn into a male when it is roughly 2-5 years old.

The geographical range of the Black Sea Bass stretches from Cape Cod to Florida where it inhabits shallow environments along the shore during the summer season. It seems to prefer rocky bottoms and is often found near reefs and man-made structures such as piers and wrecks. Each fall, the adult fish head offshore and stay in deep waters until spring.

If you want to find out more about the Black Sea Bass and how it can be grown in aquacultures, read the full article at Physorg.com.

http://www.physorg.com/news124377274.html