Tag Archives: oceanic


Shark-Free Marinas

shark free marina“We are not asking fishermen to stop fishing, only asking them to start releasing their catch,” says marine scientist Edd Brooks.

Brooks is a scientific advisor for the not-for-profit Company Shark-Free Marina Initiative, SFMI, who has just instigated a new strategy for preventing the deaths of millions of sharks belonging to vulnerable or endangered species.

The Shark-Free Marina Initiative works by prohibiting the landing of any caught shark at a participating marina. The initiative is based on the Atlantic billfish model which banned the mortal take of billfish in the 1980’s to give severely depleted populations a chance to recover.

By promoting catch-and-release and working closely with marinas and game fishing societies, SFMI hopes to win over the fishing community. Other important allies in the endeavour are competition sponsors and tackle producers.

Collaborating with the Fisheries Conservation Foundation in the USA and the Cape Eleuthera Institute in the Bahamas, SFMI has already gained the attention of marinas and non-profits nation-wide.

Enlisting the aid of anglers
By practising catch-and-release, sport fishers can not only decrease their impact on shark species; they can also actively aid ongoing research studies by collecting valuable data.

“Although the number of sharks killed by recreational fishermen each year is dwarfed by commercial catches, the current crisis facing shark stocks requires action wherever possible.” says Brooks.

During the last five years, the average number of sharks harvested annually by sport- and recreational anglers in the United States exceeded half a million. The outlook for these shark populations seem even graver when you take into account that many of the sharks targeted by fishermen are large, breeding age specimens belonging to endangered or vulnerable species. Removing so many sexually mature specimens from a population each year naturally has a major impact on its chances of long-term survival.

“Shark-Free Marinas is a necessary response to the culture of mature shark harvest” says SFMI’s Board Director, Marine Biologist Luke Tipple “Our effect will be immediate, measurable and, together with saving millions of sharks, will establish a new global standard for responsible ocean management. There’s a lot of talk about the atrocity of shark fining and fishing worldwide, but not a lot of measurable action towards reversing the damage. The time has come to stop simply ‘raising awareness’ and start implementing sensible management techniques to protect vulnerable species of sharks from inevitable destruction.”

You can find more information at www.sharkfreemarinas.com.
Help the project!

California and British Columbia sea urchins comprise to distinct populations; no connection via larval dispersal

Genetic pattern analysis strongly suggests that California and British Columbia urchins are not connected via larval dispersal and comprise two distinct populations. Sea urchins have one of the longest larval periods of any known marine invertebrate and it has therefore been tempting to assume that ocean currents must be mixing urchin larvae all over the place, making it difficult for any distinct populations to form. But research results from the University of California now indicate that these two Pacific populations are two clearly separated ones.

sea urchins
Sea urchins –  Picture from the Red Sea

Together with former* graduate student Celeste Benham, marine biology professor Ron Burton of the University of California at San Diego have analyzed 500 adult sea urchins from Californian waters across five microsatellite markers and then compared the genetic patterns to an existing, similar database of 1,400 urchins from British Columbia. The Californian specimens were collected off the coast of San Diego, Los Angeles and Mendocino counties.

The genetic signatures found by Burton and Benham strongly suggest that the southern and northern populations are not connected via larval dispersal.

“From my evolutionary perspective, our results are important because they imply that, even on long time scales, there is no mixing, Burton explains. This means there is at least the potential for populations to adapt to different ocean conditions and gradually diverge. This is the first step in the two populations potentially becoming different species.”

This is the first time scientists have detected any population structure in the species. Similar studies carried out in the past have used fewer genetic markers and found no population genetics structure in the species despite having tested many different patches across its range.

“The take-home message of this study is that if you use more markers and newer techniques you will find some population differentiation that before nobody found,” says Burton.

* Benham is now a research assistant at the marine mammal laboratory at Hubbs-SeaWorld Research Institute in San Diego.

Indonesia allows trawling in selected areas

This story might be a few days old but is still of interest and as I haven’t been able to get to it sooner I decided to post about it today.

Indonesia will allow trawling in selected areas for the first time in 30 years, maritime ministry official Bambang Sutejo announced on January 15. Trawling will be allowed off four areas of Indonesia East Kalimantan province, despite concerns about overfishing.

There will not be overfishing this time as we’re only allowing small boats to trawl, and it’s not allowed in other parts of Indonesia,” says Sutejo, adding that legalising trawling would help fight illegal trawlers.

According to Chalid Muhammad of the independent Green Institute, trawling has a destructive impact on the marine environment and will intensify the problem with overfishing in Indonesian waters. “The total amount of fish caught is getting smaller each day while their imports are getting bigger,” says Muhammad.

Muhammad also feels a legalization of trawling will embarrass Indonesia as it prepares to host the World Ocean Conference. “If the government allows this, Indonesia will have a weak standing during the World Ocean Conference as sustainable management of marine resources will be discussed,” Muhammad said. The World Ocean Conference is an international gathering of policymakers and scientists held in May 2009.

Kalimantan is the Indonesian portion of the island Borneo, the third largest island in the world, and is divided into four provinces: East Kalimantan, West Kalimantan, South Kalimantan, and Central Kalimantan.

What is trawling?

Trawling is a fishing practise where fishing boats tow long nets behind them. These nets do not only scoop up commercially valuable fish, but all sorts of marine life. Trawling is divided into bottom trawling and midwater trawling, depending on where in the water column the trawling takes place. Bottom trawling is especially harmful to marine environments since it can cause severe incidental damage to the sea bottoms and deep water coral reefs.

Orca whales returning to UK waters

Normally associated with the cooler seas around the poles, Orca whales are now becoming an increasingly common sight off the coast of UK. The Orca whale – also known as Killer whale, Blackfish and Seawolf – is found in all the world’s oceans and in most seas, including the Mediterranean and Arabian Seas. It is however known to prefer the cool waters of the polar regions, which makes this boom in recent sightings around the British Isles quite surprising for marine biologists.

orca whale

This year alone, Orca whales have been spotted in locations such the English Channel, the Irish Sea, and near Hartlepool in the North Sea. The southernmost sightings in UK waters took place near the Isles of Scilly, an archipelago off the south-western tip of England.

According to Andy Foote, PhD Student at the University of Aberdeen, pods of over 100 Orcas have been seen around the Shetland Islands this summer.

That sort of sighting does seem to be on the increase,” says Foote. “The killer whales shift their migration and distribution quite drastically. Fish like herring and mackerel seem to be doing pretty well at the moment, and it makes sense for the killer whales to follow them.”

Orca whales have been a rare sight in UK waters since fishing stocks began to decline dramatically in the mid 1900s, and the perceived increase in sightings has therefore been interpreted as a sign of recovering fishing stocks. It is however hard to know anything for sure yet, since no records of Orca sightings exists from earlier years. Researchers from the University of Aberdeen and the Sea Mammals Research Unit at St Andrews are currently monitoring the waters off Scotland, to investigate if the increase in sightings is correlated to an actual increase in Orca whales in UK waters or if it is simply the result of better recording methods.

During the second half of the 20th century, Orca sightings in UK waters have normally been viewed as transient animals migrating through the area, but researchers have now been able to determine that the same individuals are in fact recurrently spotted off the British coast, by comparing 2008 sightings with photographs taken of Orca whales over the past decade.

Until now, very little has been known about them in British waters, Foote explains. They have been considered as being transient and occasional animals that just move through the area. People thought they were very infrequent visitors. The fact that we are seeing the same ones year after year after year shows that that is wrong. Already we have highlighted that we have populations which are resident here for long periods of time, coming back to the same place, year after year after year, while some seem to remain all year around.

Paul Harvey from the Shetland Biological Records Centre agrees with Foote. “We are definitely seeing more. We know we’ve got the same animals returning and we have some occurring here throughout the winter. It is a relatively recent phenomenon. If you talk to fishermen, they just didn’t used to see them. Now, they see them every time they haul their nets. Something has gone on, since about the 1990s, when we first started to see more. We don’t know how many pods we are dealing with. That is the value of the new research.

Proper balance of herbivore fish important for coral reefs

Reef building corals rely on herbivore animals to continuously remove unwanted algae growth from them, since algae compete with the corals for both sunlight and nutrients. Without regular cleaning, corals eventually die and the reef becomes overgrown by various types of algae. A report scheduled to be published this week in the early edition of the journal Proceedings of the National Academy of Sciences now suggests that having herbivore animals present on the reef isn’t enough; there must also be a proper balance between the various species. This conclusion results from a long-term study on coral reef recovery and seaweed[1] carried out by Dr. Mark Hay, the Harry and Linda Teasley Professor of Biology at the Georgia Institute of Technology, and his co-author Dr. Deron Burkepile who is now Assistant Professor at the Florida International University’s Marine Science Program.

Different fish feed on different algae and maintaining a proper balance may therefore be critical. Of the many different fish that are part of coral ecosystems, there may be a small number of species that are really critical for keeping big seaweeds from over-growing and killing corals,” says Hay. “Our study shows that in addition to having enough herbivores, coral ecosystems also need the right mix of species to overcome the different defensive tactics of the seaweeds. This could offer one more approach to resource managers. If ecosystems were managed for critical mixes of herbivorous species, we might see more rapid recovery of the reefs.”

reef
Coral reef

The 10 month long study was carried out 18 metres (60 feet) below the surface off the coast of Florida, where Hay and Burkepile placed 32 cages on a coral reef in November 2003. At this point, the coral reef area chosen by the researchers had only four to five percent live coral coverage. Each cage was roughly two metres square and one metre tall (1 metre = 3.3 feet) and the mesh was fine enough to prevent large fish from entering or leaving the cage. The scientists then carefully selected the number and type of fish to place in each cage, using the four following combinations:

· Two fish capable of eating hard, calcified plants

· Two fish capable of eating eat soft plants that defends themselves chemically

· Both types of fish.

· No fish at all

The two species used for the experiement where the Redband parrotfish (Sparisoma aurofrenatum) and the Ocean surgeonfish (Acanthurus bahianus).

As suspected, the type of fish turned out to play a key role in the growth of algae and seaweed on the reef.

For the cages in which we mixed the two species of herbivores, the fish were able to remove much more of the upright seaweeds, and the corals in those areas increased in cover by more than 20 percent during ten months,” says Hay. “That is a dramatic rate of increase for a Caribbean reef.”

Areas with only one type of fish or no fish at all lost as much as 30 percent of their live coral coverage during the research, while areas with two species of fish increased their live coral coverage from four to five percent to six to seven percent.

Species diversity is critically important, but we are losing critical components of the Earth’s ecosystem at an alarming rate,” says Hay. “There has been little work on the role of diversity among consumers and the effect that has on communities. This study will help add to our knowledge in this critical area.”

After the initial 10-month experiment, Hay and Burkepile launched a second study where the Ocean surgeonfish (Acanthurus bahianus) was substituted with Princess parrotfish (Scarus taeniopterus). Unfortunately, the cages only stayed on the reef for seven months before being wiped away by Hurricane Dennis in July 2005.

The research was conducted at the National Undersea Research Center in Key Largo, Florida and supported by the National Oceanic and Atmospheric Administration, the National Science Foundation and the Teasley Endowment at Georgia Tech.

You can read more about Hay’s and Burkepile’s work at

http://www.biology.gatech.edu/faculty/mark-hay/ http://www.biology.gatech.edu/faculty/mark-hay/lab.php
http://www.fiu.edu/~dburkepi/front.htm
http://www.fiu.edu/~dburkepi/research.htm


[1] Seaweed is a loose colloquial term encompassing macroscopic, multicellular, benthic marine algae.

Wolffish may become first marine fish to receive endangered species protection in New England

Is the scary looking Atlantic Wolffish, Anarhichas lupus, on the brink of extinction? Today, The Conservation Law Foundation (CLF) and others filed a scientific petition with the federal government of the United States, seeking endangered species protection for this intimidating eel-like creature. If the petition is successful, the Atlantic Wolffish will be the first marine fish to receive endangered species protection in New England.

wolffish

The Atlantic Wolffish, also known as the Seawolf, is primarily found in cold parts of the Atlantic, but can also be encountered in warmer locations, such as the north-western Mediterranean Sea and the Bay of Biscay. Along the North American coast, it is found as north as the Davis Strait between mid-western Greenland and Baffin Island, and as far south as New Jersey. It is however uncommon south of Cape Cod, New England. In order to survive the cold temperature of its northern habitat, the Atlantic Wolffish has developed a natural anti-freeze that prevents its body from freezing.

The CLF petition cites federal and independent scientific studies that show a dramatic decline of Atlantic Wolffish during the past two decades. According to federal statistics, commercial fishermen are now landing 95% less Atlantic Wolffish than in 1983. Back in the early 1980s, commercial fishermen landed about 1,200 metric tones of this fish per annum, which can be compared to the mere 64.7 metric tons of Atlantic Wolffish landed last year. The Atlantic Wolffish has also worried the scientific community by virtually disappearing from the scientific research trawls carried out twice a year off the coast of New England.

Based on all available science, Atlantic wolffish are rapidly headed toward extinction in New England’s ocean waters,” said Peter Shelley , CLF Vice President and Senior Attorney. “The dramatic decline in wolffish is a troubling indication that while there is some good news about marine species like haddock and sea scallops that have been successfully restored, our ocean’s long term health continues to hang for other species by a precarious balance. Key species like the wolffish and endangered whales remain in serious jeopardy.

The main threats against the Atlantic Wolffish are commercial fishing (including by-catch) and habitat degradation, with a major part of the habitat degradation being the result of commercial fishing since it is carried out using trawls and dredges. “Absent some action to reduce or eliminate the destruction of seafloor habitat in the few remaining areas of United States waters that harbor remnant populations of the Atlantic wolffish, it is probable that it will be faced with extinction in those waters in the near future,” says marine scientist and co-petitioner Dr Les Watling.

The Atlantic Wolffish is listed as a Species of Concern by the National Oceanic and Atmospheric Administration’s (NOAA) National Marine Fisheries Service (NMFS).

Bush looking to protect more areas of the Pacific Ocean

In addition to the recently proposed areas in the Pacific Ocean, (See this and this) president Bush now says he wants to find even more regions of the Pacific Ocean to protect.

This Friday, Bush made public that he has asked the secretaries of the Interior, Commerce and Defense to identify additional areas of the Pacific Ocean that could be eligible for conservation. He also revealed that the Monterey Bay National Marine Sanctuary will be expanded by 585 square nautical miles and come to include the Davidson Seamount. Davidson Seamount is a 42 km long underwater mountain located roughly 120 km southwest of Monterey, California. The seamount rises 2400 meters off the ocean floor, but its highest point is still more than a kilometre below the surface.

Kosher caviar?

The Caspian Sea has traditionally been the world’s main source of caviar, but pollution and overfishing has caused serious problems for the fish in this enormous lake and yields are dwindling at a worrisome pace. The Caspian crisis is now prompting an increasing number of restaurants and importers to switch to Israeli caviar instead.

stugeon in pond
Sturgeon in pond – Not the facility talked about in the article

In Israel, Ossetra sturgeon (Acipenser persicus / Acipenser gueldenstaedtii) is commercially farmed at the Kibbutz Dan close to the Lebanese border, using eggs imported from the Caspian Sea. Compared to caviar from the Beluga sturgeon (Huso huso), Ossetra caviar – also known as Osetra or Asetra caviar – is firmer in texture and has the most variety in terms of size, color and flavor.

Kibbutz Dan began their Ossetra project in 2003, when caviar prices skyrocketed and made sturgeon roe even more expensive than before. The idea was not primarily to export caviar, but to satisfy the demands of the large Russian-Israeli population, according to Ben Tzvi at Kibbutz Dan. The location of the sturgeon fish farm is well chosen since it can use water from the snow-fed river Dan, a principal source of the river Jordan.

Under normal conditions, a female Ossetra sturgeon will not become sexually mature until she is around 15 years old, but Israeli biologist Avshalom Hurvitz has managed to make female sturgeons commence egg-laying at an age of just 8 or 9 years.

So, is sturgeon roe really kosher? Since the sturgeon is considered a scale-less fish, it is seen as forbidden food according to traditional Jewish dietary laws. However, according to Berta Levavi-Sivan, a scientist at the Hebrew University and a participant in the sturgeon-rearing project, the sturgeon fish is actually equipped with tiny scales – it is has only been considered a scale-less fish because the scales are too small to bee seen with the naked eye.

Fish turns out to have rudimentary fingers

According to a new study from Uppsala University, the origin of fingers and toes can be traced back to a type of fish that inhabited the ocean 380 million years ago. This new finding has overturned the prevailing theory on how and when digits appeared, since it has long been assumed that the very first creatures to develop primitive fingers were the early tetrapods, air-breathing amphibians that evolved from lobed-finned fish during the Devonian period and crawled up onto land about 365 million years ago.

Lead author Catherine Boisvert[1] and co-author Per Ahlberg[2], both of Uppsala University in Sweden, used a hospital CT scanner to investigate a fish fossil still embedded in clay. We could see the internal skeleton very clearly, and were able to model it without ever physically touching the specimen,” says Ahlberg. The scan revealed four finger-like stubby bones at the end of the fin skeleton. The bones were quite short and without joints, but it was still very clear that they were primitive fingers. “This was the key piece of the puzzle that confirms that rudimentary fingers were already present in the ancestors of tetrapods,” Catherine Boisvert explains.

The scanned fossil was that of a meter-long Panderichthys, a shallow-water fish from the Devonian period. Panderichthys is an “intermediary” species famous for exhibiting transitional features between lobe-finned fishes and early tetrapods, while still clearly being a fish and not a tetrapod. The specimen used was not a new finding; it had just never been examined with a CT scan before.

So, why have researchers for so long assumed that digits were something that evolved in tetrapods without being present in their fishy ancestors? The main reason is the Zebra fish (Danio rerio), a commonly used model organism when vertebrate development and gene function is studied. If you examine a Zebra fish, you will find that genes necessary for finger development aren’t present in this animal. Researchers therefore assumed that fingers first appeared in tetrapods and not in fish.

It should be noted that similar rudimentary fingers were found two years ago in a Tiktaalik, an extinct lobe-finned fish that lived during the same period as Panderichthys. Tiktaalik is however more similar to tetrapods than Panderichthys.

The Panderichthys study was published in Nature on September 21.


[1] Catherine Boisvert, doktorand/PhD student at the Department of Physiology and Developmental Biology, Uppsala University

[2] Per Ahlberg, professor at the Department of Physiology and Developmental Biology, Uppsala University

Can Catch Shares Prevent Fisheries Collapse?

This week, Science published the study “Can Catch Shares Prevent Fisheries Collapse?” by Costello[1], Gaine[2] and Lynham[3], which may be used as a road map for federal and regional fisheries managers interested in reversing years of declining fish stocks.

fish

The study has already received a lot of praise from environmental groups, including the Environmental Defense Fund (EDF) who says that the study shows how the overfishing problem can be fixed by implementing catch shares. “We can turn a dire situation into an enormous opportunity to promote better food security, create jobs and revive ecosystems,” says David Festa, vice president and director of the oceans program at EDF.

Catch share programs is intended to replace complex fishing rules and hold fishermen directly accountable for meeting scientifically determined catch limits. In a catch share program, fishermen are granted a percentage share of the total allowable catch, individually or in cooperatives. They can also be given exclusive access to particular fishing zones, so called territorial use rights. As long as the fishermen do not harvest more than their assigned share, they will retain a comparatively high flexibility and decide for themselves when to carry out the fishing, e.g. depending on market fluctuations and weather conditions.

The trend around the world has been to fish the oceans until the fish are gone,” says Festa. “The scientific data presented today shows we can turn this pattern on its head. Anyone who cares about saving fisheries and fishing jobs will find this study highly motivating.

As the fishery improves, each fisherman will find that the value of his or her share grows. This means that fishermen will be financially motivated to meet conservational goals.

In January 2007, a catch share system for red snapper went into effect in the Gulf of Mexico, causing the 2007 commercial snapper season to be open 12 months a year for the first time since 1990. According to EDF, fishermen in the area now earn 25% more and wasteful bycatch has dropped by at least 70%.


[1] Christopher Costello, Associate Professor of Environmental and Resource Economics at the Donald Bren School of Environmental Science & Management, University of California

[2] Steve Gaine, Professor of Ecology, Evolution & Marine Biology, University of California

[3] John Lynham, Assistant Professor in the Economics Department at the University of Hawaii at Mānoa