Thriving Oceans

photo: José Antonio Gil Martínez

Dare I say legal landings…

“From 1961 to 1973, bluefin tuna represented 45 to 80% of the U.S. western Atlantic catch of large pelagic species. Since 1980, the percentage has dropped to less than 15%, reflecting a combination of the decline in the bluefin tuna population, the impact of catch restrictions, and the increasing harvests of alternative species. Landings for 2005, 2006, and 2007 were 718, 472, and 758 metric tons, respectively.”

“Bluefin stocks remained relatively stable until the 1970s when their value soared as sushi and fresh steaks in international markets, particularly in Japan, which led to a dramatic increase in fishing effort by the U.S. and Japanese longline fleet in the Gulf of Mexico. Spawning stock biomass (SSB) saw a steady decline from the early 1970s to 1992, but after that time it has fluctuated between 18 and 27% of the 1975 level.”

 

Data: NOAA

Just a couple of recent fish/conservation related postings from JournOwl.com that I thought I would pass along…

The incredible shrinking reef fish

They say a picture is worth a thousand words and in the case of Loren McClenachan’s June 2009 publication in The Journal of the Society for Conservation Biology there is evidence of a major decline in the size of fish caught in the Florida Keys.  McClenachan used a unique method for quantitating the changes of reef fish size over the last 50 years by turning to photographic evidence and documented data of harvested trophy fish.

Read the post

Sea-cage pathogen factory: Salmon and Sea Lice

But the documentary is just a springboard into the real nuts and bolts of the fish farming issue that definitely has a marketable appeal to businessmen and everyday people concerned about overfishing alike.  Unfortunately the aquaculture solution has unintentional consequences including a decline in wild fish populations, perhaps to near extinction, in areas with high concentrations of fish farms.

According to Neil Frazer, Sea-Cage Aquaculture, Sea Lice, and Declines of Wild Fish, “The difference is that sea cages protect farm fish from the usual pathogen-control mechanisms of nature, such as predators, but not from the pathogens themselves. A sea cage thus becomes an unintended pathogen factory.”

Read the post

I came across an interview conducted by mongabay.com on marine scientist Jennifer Jacquet’s (Guilty Planet) call for some individuals to refrain from eating seafood.  It is definitely worth a read.

“I do not believe that all people should give up eating seafood. But I believe that people for whom seafood is a luxury product should consider abstaining, particularly if it is not too much of a sacrifice,” Jacquet said. “I certainly believe there should be a conservation group out there advocating this position, too, because fish need a wider spectrum of voices. Currently, almost every campaign relates to fish and invertebrates as commodities rather than wildlife.”  Mongabay.com, 2009

Considering my wife and I, for all practical purposes, have given up seafood after a longtime bout of a ban on shrimp, I wanted to expand on the comment I left on ‘A Call to Give Up Seafood.’

Fish need an animated icon akin to the panda bear that will evoke an emotional response and drive conservation efforts.  By showcasing the plight of such public-friendly creatures like birds  and whales (as you indicated), organizations and conservation efforts can also work to protect lesser known species.  With this in mind I completely agree that campaigns must equate fish/invertebrates  to wildlife as opposed to mere commodities.

Unfortunately, I have found many individuals to either be unaware of the overfishing crisis, lazy in making a concerted effort to make safe seafood choices, or simply indifferent because seafood continues to fill restaurant menus, grocery store shelves, and fish markets.

(And those who do want to be responsible are often misled by some farmed species that are eco-unfriendly.)

Perhaps it is the lack of marketable ‘spokesfish’ that has driven campaigns towards referring to fish/invertebrates as commodities. Hence, the hope is that appealing to the pocketbook of individuals, communities and commercial fisheries operations will promote long-term sustainability. But the battle still rages as fish, crabs, and a host of other species are drawn from the oceans in an attempt to quell a population’s daily appetite.
Fish and invertebrates are wildlife indeed.  Considering they draw millions of people to reefs and aquariums each year there is obviously a love of fish, but maybe it is the respect they lack.  I am a fish lover. I love to watch them forage for food, I love to watch them in shoals, I love to watch them school, I simply love to watch them interact with the environment and I find nothing better than floating in the current over a reef observing ocean WILDLIFE.  Tranquility at its best…just ask any aquarist (responsible fish keeping please!), snorkeler, and diver.  And I give them the utmost respect. 

Obviously I am not alone, but the vastness of our oceans and the continued stocking of seafood has given rise to the general population’s false sense of security that fish always have and always will be available.  Because of that it has become second nature not to give the origin of seafood a second thought.

So, does anyone have a ‘spokesfish’ in mind to expand the call for sustainable fishing practices and appeal to the masses?

Intertwined amongst the scientific publications in latest Journal of the Society for Conservation Biology is an essay harboring questions aimed at current environmental themes such as species management , climate change, and terrestrial ecosystems. The idea behind the essay, One Hundred Questions of Importance to the Conservation of Global Biological Diversity, is to evoke thoughts that will ultimately drive solutions for conservation practice and policy…in short protect biodiversity in the long-term.

And of the 100 most critical questions, 8 were organized under the section of Marine Ecosystem and are as follow:

• How will ocean acidification affect marine biodiversity and ecosystem function, and what measures could mitigate these effects?
• What are the ecological, social, and economic impacts resulting from the expansion of freshwater and marine aquaculture?
• Which management actions are most effective for ensuring the long-term survival of coral reefs in response to the combined impacts of climate change and other existing stressors?
• Which management approaches to fisheries are most effective at mitigating the impacts of fish extraction and fishing gear on nontarget species and their habitats?
• How does the effectiveness of marine protected areas vary with biological, physical, and social factors and with connectivity to other protected areas?
• What will be the impacts of climate change on phytoplankton and oceanic productivity, and what will be the feedbacks of these impacts on the climate?
• How will multiple stressors, especially fishing, pollution, sea temperature fluctuations, acidification, and diseases, interact to affect marine ecosystems?
• Which mechanisms are most effective at conserving biodiversity in ocean areas occurring outside the legal jurisdiction of any single country?

I anticipated an addressing of bycatch, climate change, and overfishing, but what I found most intriguing is the all encompassing question of the affect of multiple stressors on marine ecosystems.  This is akin to the model for the theory of everything as such an answer is the universal question.  The marine ecosystems are not defined by a single species or environmental threat, but are an interconnected world in which pollution, overfishing, bycatch, and declining biodiversity culminate in a determination of the state of our oceans.   The more stressors we continue to add to the list, the more difficulty we will have in maintaining healthy oceans.

Oyster abstinence, how ABSURD!  We can’t even practice safe-seafood.  But that may very well be our future as the list of overexploited fishes continues to grow.  This time it is not the usual suspects that populate the overfished lists such as tuna, Atlantic cod, salmon, shrimp and sharks, but a bivalve that even as far back as 1864 had been consumed in the amount of 700 million in London alone.  The details of the oyster reef demise has just been released in a Nature Conservancy report that has found 85% have been lost primarily to overharvesting and coastal development.

What I found even more astonishing, but not surprising given our history of the exploitation of fisheries and other natural resources, is the practice of shellfisheries to continue harvesting oysters to a point where only 10% of a habitat remains.  This is nothing more than a clearcutting of the oyster reef.

However, overfishing and coastal development are not the only culprits in the decline, but a systematic attack triggered by actions on land as well as sea.  The report singles out specific incidents such as transferring oysters between bays enabling  the spread of parasites and diseases, the dredging of waterways to be used for shipping lanes, the filling of bays, mangrove deforestation prompting an influx of sediment on the reefs, altering water flow from rivers, and polluted agricultural and urban runoff. But the report indicates the most pervasive problem is “…simply perception among managers that there is not a problem.”

• Oyster reefs in most ecoregions where they historically occurred are in poor condition and at risk of extirpation as functional ecosystems.
• In most individual bays and ecoregions there has been a >90% loss in oyster reef habitat. In some bays, losses are >99%.
• Globally, 85% of oyster reefs have been lost, making oyster reefs one of the most severely impacted marine ecosystem on the planet. (Shellfish Reefs at Risk, Nature Conservancy)

So unless a fundamental change is instituted for oysters, tuna, shrimp and all other targeted species, we will continue to see report after report signaling the decline of yet another item filling our seafood  counters and restaurant menus. 

And for those of you in search of aphrodisiacs, don’t worry as you can turn your attention to the plenty of other available species like rhinos, bears, tigers, sea turtles…Oh yeah, those species are facing poachers and incredible population declines as well.

www.nature.org/shellfish

I came across a piece on Fish & Aquatic News this past Sunday in which authorities in Spain confiscated 11 tons of shark fins.  It simply reminded me that the Mediterranean Sea is a poster child for overfishing and already at the mercy of an irresponsible tuna industry. Yet, what I did not fully realize was that there has been an incredible decline in sharks over the last 200 years in this region alone.
In a 2008 publication in Conservation Biology, it was found that:

“Only 5 of the 20 large predatory sharks were detected at levels of abundance sufficient for analysis. Moreover, these 5 species showed rates of decline from >96 to >99.99%, which may classify them as critically endangered according to IUCN criteria.”

Even more disturbing is that the authors contend the depleted numbers may mean the large sharks are “functionally extinct” in the Northwestern Mediterranean. So, continued harvesting of sharks only for their fins is adding insult to injury on these cartilaginous ocean inhabitants.

After a rudimentary investigation on Spain’s fishing practices, I found that most of their longlines are actually set on the Atlantic ocean side, which may be compounding the dwindling Mediterranean shark populations. Because overharvesting (i.e. 11 tons of shark fins) is taking place, we are effectively limiting the ability for Atlantic and Mediterranean sharks to replenish falling populations and/or exchange individuals via the “critical migration corridor” in the Strait of Gibraltar.

With up to 2000+ pelagic longlining boats traversing the Mediterranean Sea, a considerable illegal fisheries industry continuing operations, and lackluster regulatory action, top predators responsible for structuring  ocean communities will continue to be at under threat of extinction.

photo credit: Erik Charlton

Reference:

Loss of Large Predatory Sharks from the Mediterranean Sea, Conservation Biology
Volume 22, Issue 4, Date: August 2008, Pages: 952-964