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Creating Reefs with Tanks and Ships

Posted by Scott A. On February - 8 - 2011

Photos and article found in the February 2011 issue of National Geographic magazine, on newsstands January 25

It’s been two weeks since I found myself talking with a great crew over at the National Geographic Society.  The topic was oceans, more specifically artificial reefs, and to be honest I was begging for something to get me back in the swing of discussing our seas.  Well, 14 days later, a layover in Denver, and a swipe of the forehead for finally catching up on a backlog of graduate classes, I’m ready to engage in a little ocean diversion.

Although I have not been personally involved in the creation of artificial reefs, the idea of restoring habitat is something that I do engage in quite frequently.  And just because these restoration projects involve burrowing owls and in some cases the installation of artificial burrows, were talking about communities, ecosystems, and species.  But unlike my work in a grasslands, building artificial reefs definitely involves a stunning array of….you name it.

“Even officially sanctioned ones are often created from distinctly odd materials, including decommissioned subway cars, vintage battle tanks, armored personnel carriers, oil drilling rigs, and specially designed beehivelike modules called Reef Balls (Relics to Reefs, National Geographic Society, Feb. 2011).”

After getting past the visuals of a submerged tank or ship, there are those concerned about the impact of artificial reefs on the biodiversity of natural reefs and the potential problems of increasing overfishing.  But, I’m going to forgo jumping into that debate for the time being, and instead take a moment to share a few photos, encourage you to check out the article, and allow you to weigh the pros and cons for yourself.

Photo: David Doubilet/National Geographic

 Upholstered with luminous sponges and corals, the bridge of the U.S. Coast Guard Cutter Duane attracts schools of smallmouth grunts—and divers. The ship was intentionally sunk in 1987 off Key Largo to create an artificial reef 120 feet deep.

Photo: David Doubilet/National Geographic

 In the Flower Garden Banks National Marine Sanctuary in the Gulf of Mexico, steel pillars supporting a gas platform make a vertical reef encrusted with tube sponges.

Photo: David Doubilet/National Geographic

 This M60 is one of a hundred tanks sunk in 1994 in a 1,200-square-mile zone of artificial reefs off the coast of Alabama. The 50-ton tanks survive hurricanes better than lighter, less stable objects.

*Photos posted with permission of the National Geographic Society.

sunOur planet is an intriguing concoction of variables that meld together for successes spanning the organization of life (species, populations, communities, and ecosystems).  It is literally an evolutionary process that is ecologically driven.  And as a genotypic sex determined species, we seem to have an inherent fascination with the mysterious adaptive significance of environmental sex determination.  But the evolution of environmental conditions, such as temperature, determining the sex of offspring is not what is going to be explored at this time.  Nor do I plan to open up a heated discussion about climate change.

However, I am curious about the population dynamics of species exhibiting temperature-dependent sex determination in a warming world.  More specifically, how will sea turtle populations fare if sex ratios are dramatically skewed as a result of warmer temperatures.  Yet worry not as I am not alone in wondering about the stability of our threatened and endangered sea turtles.

Scientists from the Institute of Life Science, Institute of Environmental Sustainability and the National Marine Park of Zakynthos executed a study to determine if “temperature-dependent sex determination increases the probability of extirpation when ambient temperatures induce the production of offspring of a single sex.”  Especially when, “Some taxonomic groups, such as sea turtles, are already endangered and have sex ratios skewed to the sex produced at warmer temperatures (females).”

However, measuring population viability is more than just determining the ratio of male and female hatchlings.  Species stability requires a measurement of the number of males and females that are ready to mate at any one particular time (operational sex ratio), which also accounts for the breeding frequencies of each sex.

Results:

  • Based on hatchling ratios, it is assumed that for every 100 adult turtles in the population, there were 70 females and 30 males.
  • Males return to breed every year
  • Females breed every 2.6 years
  • Operational sex ratio is 47% female – in any particular year 30 out of 30 males will be breeding, but only 27 out of 70 females will breed.

baby loggerheadsSo just what does this data all mean?  Well, the most striking finding is that since male sea turtles breed more frequently than females (i.e. an operational sex ratio that is not female biased), they are able to “reduce the probability of unfertilized clutches.”  Even though males already comprise a smaller portion of the population, and would do so to a greater extent in a warming climate, the results are indicating that we (or they) do not have much to worry about when it comes to temperatures altering the sex ratios to a point where the population collapses.  But perhaps this just might be limited to the SHORT-TERM.

As pointed out by the authors, a male breeding cycle that is 2.6 times greater than females may help alleviate the impacts of climate change on the population, but there will undoubtedly be a reduction in males over time.  And as males become limited the probability that a population will persist declines.

For example, it is predicted that under some climate-change scenarios, nesting beaches in some parts of the world will produce only female hatchlings.  If this hatchling sex ratio propagates into adult sex ratios (e.g., there is no immigration of males from other sites), then the increased breeding frequency of males will be redundant because there will be no males.

Thus, we just may find ourselves taking on the role of the Earth’s climate by relying upon methods to control nest/embryonic temperatures in an attempt to artificially produce male hatchlings and ultimately prevent the loss of sea turtles.

ResearchBlogging.org
HAYS, G., FOSSETTE, S., KATSELIDIS, K., SCHOFIELD, G., & GRAVENOR, M. (2010). Breeding Periodicity for Male Sea Turtles, Operational Sex Ratios, and Implications in the Face of Climate Change Conservation Biology DOI: 10.1111/j.1523-1739.2010.01531.x

Humpback whale tailIt’s probably not much of a limb to go out on, but I’m pretty sure there is a clear majority and mandate by Americans to halt whaling, let alone lend official support and endorse such actions by other nations.  And I think I may enter the frigid waters and tackle our own policies regarding indigenous harvesting in another setting.  For now, I like to imagine that the approval rating for whaling is somewhere in the single digit range, but after reality sets in I doubt we have yet to reach the incredible homogeneity that the populace of Australia has been demonstrating.  As reported by Time, ” A national poll conducted in January [2010], 94% of Australians said they were against whaling.”

As for the U.S., the numbers I have on hand are two decades old, but it does speak to our disdain for a practice that seems only fitting for 160 year old novels and blurry monochromatic photos adorning museum walls. The poll found that 83 percent of American voters oppose killing whales, 61% “strongly” oppose whaling, 82 percent want government officials to speak out publicly against commercial whaling, and 55% believe the U.S. government should impose limited trade sanctions banning the import of seafood products from countries that continue whaling (Schoen & Berland Associates 1999).

Now that a new proposal to lift the ban on commercial whaling is making headlines, I am wondering if the voices of the American people are simply being ignored…again.  And I think there really might be a disconnect between governments, the International Whaling Commission, and the people when it comes to this particular issue.  WHALES ARE NOT ANIMALS.  And I think most of us inherently understand this ideology and have a connection to cetaceans that far surpasses something that can simply be chalked up to the love for a high profile, charismatic species.

So for those wondering what whales are if not simply animals, the answer is a BEING.  We are human beings and they are whale beings; it’s an existential connection based on mutual respect, based on intelligence, and based on the fact that we see us in them.  Yet it is so much more than mere anthropomorphism as I/we embrace them as colleagues in life.  Thus, many of us perceive whaling as an antiquated notion, whether or not done under the guise of scientific permits.

Now that we have established a background, it’s time to circle back to the proposal to end a ban on whaling.  In March 2010, the International Whaling Commission (IWC) produced a draft proposal to address:

…the problems within the Convention; conservation and sustainability; healthy whale populations; exploitation and protection; whaling under special permit (‘scientific whaling’); small type coastal whaling; benefits for developing countries; monitoring and accountability; sanctuaries; the commercial whaling moratorium; an interim period; governance mechanisms of the IWC; animal welfare; aboriginal subsistence whaling; international trade; reservations and objections; whale watching; bycatch and human impacts; small cetaceans; an acceptable “Package”.

whaling-iwcAddressing problems is always a good thing, right?  Well, after waving away the smoke we find that the proposal not only recommends whaling for members of the IWC who are currently killing whales to legally do so for the next 10 years, but that the Obama Administration is backing the plan (Which by the way was announced in a press release on Earth Day 2010).  Additionally, the key is an “acceptable package,” which can be argued as strictly no whaling,  and is currently tied to the fact “that whaling catch limits are largely still to be determined.”  It is because of this ambiguity in the draft proposal that the International Fund for the Welfare of Animals (IFAW) is looking for support and involvement. 

“The plan can mean not only reversing the current ban on whale hunting by Norway, Iceland, and Japan for the next ten years, but will allow whaling in the internationally recognized whale sanctuary around Antarctica.” IFAW 2010

 Thus, I caught up with Chris Cutter, IFAW spokesperson, to find out a little bit more about this developing situation as they fight to protect a species in which we have so much in common.

Thriving Oceans:  What is your main concern with the new proposal and the backing by the current Administration?

Chris Cutter: Our main issue is that the administration is saying definitively that this deal would save X numbers of whales. The issue is that the current proposal has “draft” numbers in it.

 You could take the administration at face value and say the “intention” is to reduce the numbers of whales killed, but it’s inaccurate to say that the proposal would save X amount of whales without any hard figures to back that up.

Thriving Oceans:  Are we potentially jumping the gun by criticizing a draft proposal?

Chris Cutter:You could flip that around and say it’s inaccurate for IFAW and other NGOs to criticize the plan for the same reasons. Without any numbers it is impossible to assess. Suffice it to say, given the history of the negotiations to date, the structure of the proposal itself, and the fact that all of the conservation benefits are based on dubious science, we’re skeptical.

 Thriving Oceans:  So we’re potentially hearing some environmental pandering as the Administration is claiming whales are going to be saved?

Chris Cutter:  The problem is that there will be hard numbers in the proposal when it is voted on next month. Until those numbers are written in ink, not pencil, no one should be talking about future numbers of whales killed or saved.

It is up to us to lead the effort in protecting these animals.

To learn about how you can get involved, please visit IFAW on Facebook or visit www.IFAW.org.

nwhi-sharkI’ll be perfectly honest…I’ve been sitting on this essay from Conservation Biology for the last week or so as I mulled over my approach on breaching this topic.  At one point I envisioned the title as Torn Between Ocean Science and Ocean Conservation; clearly a manifestation of the dilemma with which I was trying to come to terms.  The direction we go just seems so obvious, right?  Well I guess that depends on which side of the fence you fall on as the authors, Heupel and Simpendorfer,  do a fairly good job at covering all aspects of the issue, from allowing scientific collection of only healthy species to limited collections of endangered species to the use of non-lethal methods to use of collections only in an attempt to perfect non-lethal sampling methods.  So what SHOULD we choose? 

Whether good or bad scientifically speaking, the fact is that continued media coverage of declining shark populations and our fisheries in general is sparking a change in the attitudes of our future scientists as conservationist ideals seep into the public.

“One noticeable result of the increase in concern about sharks is that more students enquiring about graduate school who are interested in working on sharks are indicating they are not willing to participate in projects that may harm sharks. This occurs before they know which species are involved, the status of that species, or what benefits could be gained from lethal sampling. This suggests their perspective is not rooted in science, but is ethical, political, or emotive.”

dusky_shark

So are ethics, politics, and emotions incompatible with science?  Perhaps.  But before any skewering takes place let me qualify that remark.  Science strives or should strive to remain unbiased  in its approach to answering questions or interpreting results.  Science should not let politics drive a conclusion, science should not let profits mask facts, science should be done responsibly, and science should not be performed when devoid of morality.  And if this is the case, then I think it is obvious why we find ourselves with up and coming scientists displaying perspectives rooted in wildlife and ocean preservation.  Our ethics and emotions are driving those interested in marine conservation to take the lead for the protection of ecosystems as next generation scientists.  And when we combine this with garbage filled oceans, oil spills and pollution, and overfishing ,for instance, it should not be surprising that those tired of ocean degradation are interested in making a positive difference.   

sharkessay-quoteAnd let’s not forget that we apply such a social standard when it comes to research on whales.  Non-lethal sampling is a worthy endeavor and out of scientific necessity ingenuity will drive new and innovative data gathering methods.

This definitely goes beyond sharks and speaks to greater societal attitudes. There’s a problem and our oceans need fixing.  And I am hoping that this change in attitude is not limited to those aspiring to be ichthyologists and marine biologists, but highlights growing awareness amongst consumers.  Getting back to the issue on the table, sharks are declining worldwide because of finning, commercial and recreational overharvesting , and loss of functional habitat to name a few.  But what does this all mean for science?  Well the authors ask the following questions:

“Should research sampling be slowed, stopped, or questioned because of their status?”

“Is the preservationist’s point of view misguided because information on depleted species is being applied to all shark populations?”

“Thus, if shark species are not assessed accurately and scientifically and suffer from biases, how can effective management and conservation be applied?”

I think one thing that is clear is that the answers or reasons will be just as varied as the life amongst a coral reef. But in regards to Heupel and Simpendorfer, the answer is rather middle of the road in that they believe we should not forego compiling data nor completely condemn killing sharks in the name of responsible science.  Additionally, they recommend always taking appropriate precautions to use nonlethal approaches whenever possible. However, this is just conjecture as I guess the actual solution will be determined in the near future by those now entering the scientific field.

ResearchBlogging.org
HEUPEL, M., & SIMPFENDORFER, C. (2010). Science or Slaughter: Need for Lethal Sampling of Sharks Conservation Biology DOI: 10.1111/j.1523-1739.2010.01491.x

Atlantic Bluefin Tuna: Conservation Thwarted by Profits

Posted by Scott A. On March - 18 - 2010

Photo: Captive bluefin tuna inside a transport cage.  Credit: Gavin Newman / European Pressphoto Agency

An organization that delegates [tries to] policy without any foreseeable recourse at their disposal is simply a Think Factory.  They ‘THINK’ they can get offenders to comply merely on the basis of suggestion.  Perhaps this tactic works in the world of science fiction when the wave of a Jedi’s hand is all that is needed to persuade the weak minded to act in accordance, but on this blue planet it’s the greenery that ‘s the driving force.

As per PhilBee’s recent comment  on the posted video “A Ban on Bluefin Tuna?”,

Therein lies the major problem with the whole system: if a country wants to catch a particular species, it knows it can do so without fear.  Japan’s done it for years with whales, and intends doing it with Atlantic bluefin tuna until stocks are gone.

When you combine short term philosophies with big profits now, we find ourselves constantly hovering on the brink of a catastrophe.  Yet we dismiss the blatant warning signs in an inane refusal to admit a problem is brewing because wallets continue to grow.  And this global trend of denial spans Wall Street, the housing market, whales, salmon, bluefin tuna, sharks, and the list goes on and on.  Are we so short sighted that we cannot make the historical connections?  The age old saying describing those who do not  learn from history are condemned to repeat it is not just a cleaver witticism is it?

Well, we again find ourselves nodding in shame that organizations designed to protect global resources have managed to fall short of garnering enough protections to ensure sustainability.  But, it is not the sole fault of the United Nations or the International Whaling Commission to eradicate the problem.  It is the consumer behind the iron mask that is completing the profitable circle, continuing to order fish species plagued by depleted stocks, and are thus responsible for contributing to the overharvesting problem .  Making responsible choices is of the utmost importance and is quite necessary for conservation.  And of course that does not let negligent industries, businesses, and nations off the hook who continue to practice and promote unsustainable fishing and poaching practices.

So what we end up with is a lack-of-action scenario that is aptly manifested by an AP quote in “UN rejects export ban on Atlantic bluefin tuna”:

“Let’s take science and throw it out the door,” said Susan Lieberman, director of international policy with the Pew Environment Group in Washington. “It’s pretty irresponsible of the governments to hear the science and ignore the science. Clearly, there was pressure from the fishing interests. The fish is too valuable for its own good.”

Those concerned for ocean conservation must continue to educate friends and family, spread the word, make responsible consumer choices, and continue advocating sustainability.   While we fight for better legislation and protections, it doesn’t hurt to hit them where it hurts…their pocket books.

 

Photo: Captive bluefin tuna inside a transport cage. Credit: Gavin Newman / European Pressphoto Agency

Declining Parrotfish Instill Hope but Highlight Human Flaw

Posted by Scott A. On December - 1 - 2009

While rummaging through the latest research in Conservation Biology, I came across a publication that caught my attention.   It’s not that the title conveyed a trinket of enlightenment nor promised to do so as I wound my way from introduction to methods to discussion.  In fact, the title evoked an emotional response that was the exact opposite of astonishment.  And by that I merely mean I could (or assumed I could) foresee the results, which is practically a staple in the ocean conservation world when discussing the effects of a burgeoning coastal human population on neighboring marine ecosystems.  In that context, is there anything else that should pop to mind other than overfishing and declining fisheries? 

Credit: Richard Ling

But, I will admit that my curiosity was peeked as it is my first encounter with parrotfish headlining the research.  So, I decided to move forward and examine the text behind the title, “Implications of Urbanization for Artisanal Parrotfish Fisheries in the Western Solomon Islands.”  Perhaps the title’s key words like ‘urbanization’ and ‘fisheries’ are dead giveaways, but remember this is a scientific publication and not the latest thriller in the midst of protecting a multi-level plot twist for the sake of sparking revenue.

With the pages rolling it becomes quite apparent that there are a few conservation gems sprinkled throughout the paper and worthy of rehashing, or what a waste of my time in writing and yours in reading this post.   Success of marine protected areas, declining species, and the interconnectedness of species in an ecosystem are the themes/take home messages while the family Scaridae is the star, or victims, of the show. 

neg_quoteScarids, or parrotfish, included 83 species at the time of my university courses (~90 species as of 2002) and are so named because their fused teeth resemble a parrot-like beak.  And it is this beak that is quite useful for biting off pieces of coral and algal fronds.  The bits are ground down in their massive pharyngeal mills and the algal cells are extracted.  As discussed by the authors, parrotfish fill a critical role in maintaining coral reef systems by controlling filamentous algae and Scleractinian corals, removing detritus, and digging through the surface of the reef thusly redistributing the ground calcareous pieces as sediment.

As Pacific Island populations grow, the demand for coral reef resources including the parrotfishes themselves increases dramatically.  Thus, it is not surprising that the fishing pressures have caused a total parrotfish population decline of 45% from 2004 to 2005 in the Pacific Island study area. But remember I said there were a few conservation gems…well it turns out communities in the Western Solomon Islands have begun to see the frightening trends and instituted management practices and community-based marine protected areas to curb the overfishing (and habitat degradation) problem.  Not only are their livelihoods on the line but the whole coral reef system.

The take home lesson is that community-based marine protected areas do in fact work, and is evident with the following results:

 -Parrotfish numbers/abundance in outside sites were significantly lower than inside community-based marine protected areas (CBMPA) for each size category.

-Large effects between inside and outside CBMPAs were evident in each size category.

-Combined, these findings reinforce the stark difference in abundance across fish size categories between inside and outside the CBMPAs of villages with customary management and an urbanized center.

Photo: Richard Ling

We now have yet another piece of evidence highlighting the need for marine protected areas to ensure healthy fish populations and coral reefs, as well as a need to conserve for the future health of a growing human population.  However, instilling good ocean management practices is not and an idea we can afford to treat with procrastination.  According to the authors, “There is a negative correlation between effective conservation and human population size (beyond a threshold of more than 1000 people) and between market integration and wealth, which suggests that as rural communities urbanize and monetize in Melanesia, their capacity to conserve resources weakens.”

And this negative correlation is perhaps the most interesting finding and something that sounds quite familiar.  As populations grow and become more economically viable they effectively lose their ecological self-control and ocean husbandry suffers. 

So is this humankind’s innate progression as we become less reliant on the natural course of the environment and aim to control it?  I have definitely seen this trend before…Have you?

This post was chosen as an Editor's Selection for ResearchBlogging.org
ASWANI, S., & SABETIAN, A. (2009). Implications of Urbanization for Artisanal Parrotfish Fisheries in the Western Solomon Islands Conservation Biology DOI: 10.1111/j.1523-1739.2009.01377.x
Photo credits: Richard Ling



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