Analysis of a drop chain trawl as a method of bycatch reduction with squid, skates, and flatfish

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By Brenna Bales, SRC Intern

It is no secret that bycatch is a huge problem threatening the health of the oceans. Gillnets, longlines, and trawl nets often capture many more unintended species than what is originally sought after. In order to reduce this extremely wasteful practice, it is imperative that new systems and new technologies be created to find a solution. Here, Bayse et al. (2016) tested the viability of drop-chain trawls as a tool to reduce bycatch.

The ground-gear rigged to the trawl net included rubber disks and rollers, designed to prevent the catch of any unintended benthic species.

The ground-gear rigged to the trawl net included rubber disks and rollers, designed to prevent the catch of any unintended benthic species.

Drop-chain groundgear, configured beneath a trawl net for this experiment, was determined to be effective at reducing bycatch in the Nantucket sound squid fishery off of Cape Cod, Massachusetts, USA. Longfin inshore squid (Doryteuthis pealeii) are the intended catch in the surrounding waters, however summer flounder (Paralichthys dentatus) and skates (family Rajidae) are two species that often find their way into the trawls as bycatch. Concerns have been raised throughout the area’s other fisheries that the use of this new system’s heightened foot-ropes will result in a lower catch due to squid escaping underneath the fishing line. However, this system is designed to take advantage of the benthic behaviors of the bycatch species during the trawling process (Ryer, 2008; Winger et al., 2010), without compromising the ability to capture squid.

Methods

On the 16th and 17th of June, 2012, four tows were conducted aboard the F/V Atlantic Prince. Underwater video was recorded using an HD GoPro in shallow, clear water during daylight hours. The camera was placed in the trawl at the top of the net, facing forward and slightly down towards the mouth of the trawl. From the recordings, the following events were quantified: entrance into the trawl or escape underneath the fishing line and between drop-chains, contact/impingement between animals and ground gear, swimming behaviors, positions, orientations and time in trawl mouth. These behaviors were subsequently assessed as to whether the capture or escape of the animal resulted.

Hundreds of fish accidentally caught in the net of a shrimp fishery, June 1969. Source: Wikimedia Commons.

Hundreds of fish accidentally caught in the net of a shrimp fishery, June 1969. Source: Wikimedia Commons.

Results

A total of 2,532 individual squid were observed, of which zero escaped. 99.0% of squid were oriented with their mantle in the direction of towing. As for summer flounder, 87 total were observed, however 44 had an unknown capture outcome. Of the 43 whose capture outcome was known, 26 entered the trawl and 17 escaped. 76.7% of the flounder changed direction as they were swimming, subsequently entering the trawl. Last but not least, 197 skates were observed at the mouth of the trawl, of which 175 escaped. 91.8% of all skates were oriented in the same direction as the trawl.

Outcomes

From these results, it was determined that the modified drop-chain trawl, specifically modified to accommodate the behaviors of the bycatch species, was effective in reducing the number of skates caught, but ineffective for reducing summer flounder bycatch. In addition, it did not compromise the ability of the net to catch squid. All in all, this is just one method of bycatch reduction that has proved successful. In combination with several other methods, such as larger trawl mesh sizes, or the use of grids, we can reduce the harmful impact of other commercial fisheries.

References

Bayse SM, Pol M V, He P (2016) Fish and squid behaviour at the mouth of a drop-chain trawl: Factors contributing to capture or escape. ICES Journal of Marine Science, 73, 1545–1556.

Ryer, C. H. 2008. A review of flatfish behaviour relative to trawls. Fisheries Research, 90: 138–146.

Winger, P. D., Eayrs, S., and Glass, C. W. 2010. Fish behaviour near bottom trawls. In Behaviour of Marine Fishes: Capture Processes and Conservation Challenges, pp. 67–103. Ed. by P. He. Willey-Blackwell, Ames, IA.

Herring Perform Stronger Collective Evasive Reactions when Previously Exposed to Killer Whale Calls

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By Shubham Mathur, SRC Intern

The ability of large schools of marine fish to react to predatory behaviors with high levels of coordination. Forming a school and synchronized swimming are used to reduce the risk on any individual, and to detect approaching threats.

Image 1_Clupea_harengus_Gervais

Atlantic herring (Clupea harengus)

The Atlantic herring (Clupea harengus) is an example of a species that forms large schools. Like many species of small pelagic fish, the Atlantic herring is a vital source of prey for many larger marine species, including fish, sea birds, and even marine mammals, all utilizing different methods of predation. As hunting pressures are never constant, the little herring must adapt its predation evasion tactics to combat whatever form of predator is most prevalent at the time. One of the primary predators of the Atlantic herring in the Norwegian Sea, is the killer whale, or orca (Orcinus orca).

Image 2_1200px-Killerwhales_jumping

Two orcas (Orcinus orca) breaching

Highly vocal creatures, orcas coordinate groups to feed on the schools of herring. While it is known that orcas often use their calls to herd the schools of herring into tight formations to facilitate predation, it is not known if or how the Atlantic herring can make adjustments to schooling behavior to minimize the risk of orca predation. Testing the idea requires observing the fish in as realistic of a scenario as possible.

Image 3_Large_fish_school

Large school of small pelagic fish

An approximately 14-tonne school of wild-caught herring was placed into a large sea cage used for aquaculture. The 12 by 12 by 12 meter cube was located at the Institute of Marine Research aquaculture facility in Austevoll, Norway. In this set up, orca calls were played via underwater speaker for the fish in the cage. Additionally, a black predator model was built and pulled across the cage below the surface.

After the experiment was completed, it was concluded that while the school of Atlantic herring did not modify their school structure as a response to orca calls alone, they did perform a stronger collective escape response when the fish had been exposed to the vocalizations. While it was previously thought that the structure and organization of a school of wild pelagic fish was organized based on predator evasion tactics, in this case this was not found to be the case, and that the greatest behavioral change was found in the escape response of the school during a predatory event.

References

Durban, By John. “National Marine Mammal Laboratory (NMML).”Quarterly Research Reports for National Marine Mammal Lab, April-June 2005. N.p., n.d. Web. 20 Oct. 2016.

By Gervais et Boulart – Les poissons Gervais, H., Public Domain,

Durban, By John. “National Marine Mammal Laboratory (NMML).”Quarterly Research Reports for National Marine Mammal Lab, April-June 2005. N.p., n.d. Web. 20 Oct. 2016.

By OpenStax College – [1], CC BY-SA 3.0,

ICZM in Cuba: Challenges and Opportunities in a Changing Economic Conext

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By Andriana Fragola, SRC Intern

This paper discusses the problems and shortcomings hindering proper functioning of Integrated Coastal Zone Management (ICZM) initiatives in Cuba. ICZM began in Cuba in 1992 after the Earth Summit meeting. However, planning documents have not taken the structure of the Cuban government into account, making it difficult to implement this new management strategy.

Enhanced environmental policies were established in Cuba in the 1990s, focusing on sustainable energy, environment and socio-economic development. To manage more sustainable development, the Cuban government created the Ministry of Science, Technology and Environment (CITMA), and the National Environmental Strategy (Gerhartz-Abraham 2016). Later, in 2000, the Coastal Zone Management Decree Law 212 became the major source of regulation for coastal ecosystems including wetlands, mangroves and coral reefs (Gerhartz-Abraham 2016).

Cuba's maritime zones

Cuba’s maritime zones

Installing ICZM in Cuba is crucial because it has exceptional biodiversity and is the largest island nation in the Caribbean. Cuba’s ocean accounts for about 48% of its jurisdictional area, and encompasses about 7% of the world’s total coral reefs (Gerhartz-Abraham 2016). There are many estuarine habitats such as seagrasses and mangroves which act as a refuge for multiple organisms during their juvenile growth periods. Cuba also receives many economic benefits from these ecosystems through medicine, fishing, tourism, and a source of food (Gerhartz-Abraham 2016).

The National Environmental Strategy concluded that soil erosion, deforestation, pollution of inland coastal waters, loss of biodiversity, and habitat degradation are the main problems the Cuban marine ecosystems face (Gerhartz-Abraham 2016). Fishing is another very important issue the Cuban reefs are currently stressed from – through overexploitation of fish, habitat damage from fishing gear, and bycatch (non-target species caught – and usually killed – during fishing).

When examining the Coastal Zone Management Decree Law 212 and enforcement of it’s regulations, one of the problems facing Cuba is that the document never explicitly details how to implement these environmental plans specifically for Cuba’s circumstances. There is also a lack of resources in Cuba to incorporate these management policies, as well as an absence of a systematic approach in the establishment and incorporation of new legislation (Gerhartz-Abraham 2016). These gaps and inconsistencies between government and political action greatly hinder the Cuban government’s ability to establish these protocols. Without addressing these issues, it will be challenging for Cuba to establish effective coastal zone management.

Coral reefs along Cuba's coast (Montaigne, F. 2015)

Coral reefs along Cuba’s coast (Montaigne, F. 2015)

In an effort to mitigate these conflicts, workshops with members of the Cuban government, coastal community members and ICZM experts have been held, making recommendations of ways to make these new regulations work, and assessing key indicators to assess how effective the plans have been (Gerhartz-Abraham 2016). There is also encouragement for local stakeholders to take part in the decision-making and development, as well as an to integrate across levels of government, creating cooperation, transparency and co-management (Gerhartz-Abraham 2016). If effective changes are made after addressing these main issues, the Cuban government will be able to protect their coastal ecosystems allowing them and their economy to synergistically thrive.

References

Gerhartz-Abraham, Adrian, Lucia M. Fanning, and Jorge Angulo-Valdes. “ICZM in Cuba: Challenges and opportunities in a changing economic context.” Marine Policy 73 (2016): 69-76.

http://e360.yale.edu/slideshow/along_cubas_coast_the_last_best_coral_reefs_in_the_caribbean_thrive/426/1/

Trade-offs Between Energy Maximization and Parental Care in a Central Place Forager, the Sea Otter

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By Trish Albano, SRC Intern

Energy expenditure is a key component to consumer foraging strategies. In this study, the influence of prey availability and reproductive limitations were examined, in an effort to determine their impact on the foraging behavior of the southern sea otter (Enhydra lutris nereis). Theoretically, when food is plentiful, it is energetically efficient for a central place forager to exploit prey patches that are closest, therefore minimizing energy expenditure and conserving metabolic rate. The study predicts that as prey becomes more scarce, otters will dive deeper to find prey and the associated energy expenditure will be proportionately greater. Due to the physiological differences between males and females, the study predicts that males will show a greater range of dive depths and durations but both sexes will respond to prey scarcity in the same manner. The demands of pup care in females are also taken into account – it is hypothesized that if pup care plays a significant role in females’ diving behavior, mothers with small pups will stray from normal responses to food scarcity the most because deep, long dives could increase the likelihood of pup loss.

Mother sea otter with rare twin baby pups, presumed to have been born just one or two days earlier on June 23-24, 2013. Photo taken 24 June 2013, Morro Bay, CA. AKA Southern sea otter and California sea otter, Subspecies E. l. nereis, Coast of Central California. Wiki http://en.wikipedia.org/wiki/Sea_otter

A mother and pup Southern Sea Otter (E. I. nereis). It has been shown that mother sea otters put a considerable amount of energy into the parental care of their pups. Image credit: Wikimedia Commons

Methods

The researchers utilized TDRs (time-depth recorders) implanted in wild southern sea otters to collect data in 5 locations (Figure 1) (Monterey, Big Sur, San Luis Obispo County, Santa Barbara Channel, San Nicolas Island) along the California coast. TDRs stayed inside the animal for approximately 1 year. Most animals were observed from shore for behavioral data collection and it was noted that across all 5 sites, otters fed on 80 different species of benthic invertebrates. Both resource abundant (low otter density, high food density) and resource deficient (high otter density, low food density) sites were explored.

Figure 1: This figure shows the 5 sites that data was collected for Southern Sea Otter populations. In these locations, otters were fitted with TDRs and observed for study.

Figure 1: This figure shows the 5 sites that data was collected for Southern Sea Otter populations. In these locations, otters were fitted with TDRs and observed for study.

Results

When prey was scarce, otters expanded their selection to include less-preferred prey. It was found that males and females without pups utilized similar foraging strategies and responses to food limitation, making deeper, longer and more energetically costly dives as prey became more scarce. However, females with pups were less likely to exhibit these energetically inefficient diving profiles. Mothers with young pups (less than 10 weeks old) placed parental care at higher priority than foraging when resource limitation would require them to perform energetically expensive dives that would reallocate their energy usage away from their pups. Females without pups in resource-abundant areas made 54% of dives to 2-5 m and 25% of dives to 6-10m whereas females with young pups made 3% of dives to 2-5 m, 52% of dives to 6-10 m, and 29% of dives to 11-15 m (Table 1). This trend of greater-proportion deeper dives was similar in resource-limited areas. This shows that females with pups utilized their energy in such a way that made it worth their while to leave their pups alone if there was a higher likelihood that they would be able to access food during their dive. Overall, the researchers’ hypotheses were supported by the data.

Table 1: This table shows the summary for TDRs that were used to obtain data in the study. The TDRs are site specific and measure resource availability, age range, median age, years of deployment, and duration of TDR recording.

Table 1: This table shows the summary for TDRs that were used to obtain data in the study. The TDRs are site specific and measure resource availability, age range, median age, years of deployment, and duration of TDR recording.

Outcome

This study shows that prey availability is critical for all southern sea otters, but especially for mothers with pups. If resource abundance is depleted, it can become very risky and energetically expensive for otters to forage. This could cause an increase in pup mortality and become a threat to southern otter populations.

Resources
Thometz, N. M., et al. “Trade-offs between energy maximization and parental care in a central place forager, the sea otter.” Behavioral Ecology (2016): arw089.

Why do Fishers Fish?

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By Emily Rose Nelson, SRC Graduate Student

Humans have been fishing for over 40,000 years. Initially, the world’s waters were thought of as a resource with no bounds. However, intensification of fishing pressure over the last 100 years has decimated fish populations, forcing us to realize that the oceans’ resources indeed do have limits. Today, fish make up more than 16 percent of the global human protein intake, whether it is in the form of subsistence fishing in developing countries or extravagant restaurants in wealthy countries. As demand for marine resources continues to grow, pressure on fish populations is also increasing. Governments around the world have started making efforts to slow the decline of ocean resources, but in many cases the success of these initiatives is dependent on compliance of the fishermen. Essentially, conservation efforts are in direct conflict with fisher objectives. For this reason, it is important to understand why a fisher is fishing in the first place – knowledge of fishers’ motivations will help policy makers identify the most effective conservation methods.

Young et al. 2016 set out to answer the question, “Why do fishers fish?” using an ethnographic approach. They conducted semi-structured interviews of experienced male fishermen at two sites, Australia and the Solomon Islands. The interviews gathered information about their general background, fishing methods, motivations for fishing, and feelings upon return from a fishing trip.

The interviews identified an overwhelming split in motivation to fish between the two study sites. 100 percent of fishers in the Solomon Islands were motivated by food and 93 percent were motivated by income. In contrast, 96 percent of the fishers in Australia were motivated by a connection to the environment. Recognizing these differences in incentives can help managers to form the best conservation policy for each region. For example, one could not realistically set in place a no-take marine reserve throughout the Solomon Islands without providing the fishermen and their families with an alternate source of food and income.

Motivations for fishing in Australia (gray bars) and the Solomon Islands (black lines).

Motivations for fishing in Australia (gray bars) and the Solomon Islands (black lines).

Despite the drastic difference in ‘primary reason to fish’ between the Solomon Islands and Australia, interviews revealed that many other drivers were the same. When fishers in the Solomon’s were given a hypothetical situation in which they had secured an alternate income, 100 percent of interviewees indicated that they would still continue to fish whenever possible. This shows that the fishers are getting enjoyment out of their work and indicates the presence of a somewhat recreational mindset. Therefore, if economic conditions were to improve in the area there would likely be a growth in recreational fishing. In Australia, where recreation is the primary reason for fishing, 80 percent of fishers identified food as a secondary incentive. For those people, fishing provides an escape from their stressful day to day lives, with the added bonus of catching a fresh meal for a price much cheaper than what is available at local fish markets.

Young et al. were not only able to identify clear-cut cultural differences in fishing motivations, but also recognize that fishing may provide benefits to individuals and communities that transcend these traditional motivations. In both the Solomon Islands and Australia, mentions of social bonds with fellow fishers and camaraderie were widespread in interviews. Lastly, the interviews revealed that fishing might not be as far off from conservation as some may think. The values identified of many fishers in this study, such as “teach children to appreciate nature” and “foster respect for the environment” are very similar to those of conservationists. As said by an Australian fisher, “fishing provides environmental benefits because we like to protect things that are dear to us.”

References

Young, A.L., Foale, S., & Bellwood, D.R. (2016) Why do fishers fish? A cross-cultural examination of the motivations for fishing. Marine Policy, 66: 114-123.

Harnessing the Power of the Web as a Tool for Conservation, Not Sensation

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By Kevin Reagan, SRC Intern

Meet the pygmy slow loris, one of the world’s most threatened primates and star of one of the most popular animal videos uploaded to YouTube. The video featured Sonya, a female pygmy slow loris, being tickled in a bedroom in Russia. It accumulated 9,338,000 views between April 2009 and January 2012 (when it was removed due to animal rights concerns) and received 12,411 comments over that time (Nekaris 2013).  Since pygmy slow loris’ are endangered, trade in any of the eight species is prohibited by CITES, and it is illegal to keep them as pets. With the dawn of the digital age came the birth of a world that is constantly plugged in, and the video being uploaded to YouTube brought people into contact with an animal that many of them, based on the analysis of the comments left on the video, had never even heard of (Nekaris 2013). This is just one of the many direct examples of the ability of the web and the media to influence public opinion. One in ten people that commented alluded to wanting a slow loris as a pet, either ignoring or ignorant to the fact that it is illegal. The web and media as a whole have an unmatched ability to influence public opinions and perceptions. Though the effect is not always negative, many times news outlets around the world fall short when it comes to covering conservation issues and negative human-animal interactions.

Individual pygmy slow loris.

Individual pygmy slow loris.

The sad reality of today’s 24-hour news cycle is that sensational headlines, while they may not reflect the true, factual nature of the story, generate more money for news organizations simply because they receive more attention. Sensational headlines can be thought of as headlines that present the world as hostile or threatening (McLeod 588). In other words, attention-grabbing. These can have a noticeable effect on public opinions, especially when it comes to animal conservation and risk perception of large predatory species such as bears, coyotes, or sharks that are occasionally part of negative interactions with humans. Unfortunately, these interactions usually result in injury to the person involved, or in some cases death. However, headlines are not the only issue; many times, articles and stories focus on the more “exciting” aspects of certain animals (e.g. attacks) rather than other issues facing those same animals, like conservation threats. Unfortunately, more articles focus on the threats that animals pose to humans rather than the threats that humans pose to animals.

Even though journalists in general are trained to give readers as much background information as they can (in order to tie together their main story with solid information and place everything in an accurate context for the general public), the time-driven aspect of news prevents this more often than not (Boyer 123). When a story breaks, journalists have a limited amount of time to write an article and get it out to people; not only are they under pressure from deadlines, but if they wait too long, the story may be reported by another news agency, or simply become old news. Because of this, articles and stories concerning things like shark attacks many times do not have input from the shark researchers or conservationists that could round out the story and place it in an entirely different context (Boyer 123-124).

Early newspaper with a sensational headline reading “Jersey Shark-Hunters Out for Big Man-Eaters on Jersey Coast.” This was written in response to a string of shark attacks off the coast of New Jersey in the early 1900’s.

Early newspaper with a sensational headline reading “Jersey Shark-Hunters Out for Big Man-Eaters on Jersey Coast.” This was written in response to a string of shark attacks off the coast of New Jersey in the early 1900’s.

A 2013 study of Australian and U.S. news media portrayal of sharks and their conservation found that even though there is a substantial amount of evidence indicating that many shark species are at risk, shark attacks were reported five times more often than conservation concerns or any shark-related topic in both Australian and U.S. media. Authors write that “Social framing of sharks as either

victims or perpetrators may lead to assumptions about policy prescriptions (e.g., help the victim, persecute the perpetrator) (Muter et al. 2009). If sharks continue to be framed primarily as perpetrators of risk, policy responses will likely remain unfavorable to shark conservation”(Muter 194-195). The message of movies such as Jaws and Deep Blue Sea or headlines that say things like “Dolphin saves swimmer’s life when great white shark appears” give sharks, especially the great white, a negative public image. The headline implies that once the shark appeared its single goal was to attack and eat the swimmer and by some stroke of luck a dolphin fought off the shark, even though that is not the case. This type of reporting, combined with sharks’ exceptional susceptibility to human related pressures, is bad news for shark conservation and protection worldwide.

Sharks are not the only animals that receive media attention. On August 19, 2002, a black bear in Sullivan County, New York, fatally injured an infant at a summer bungalow colony. The bear was subsequently hunted down and killed, and the event received coverage on local, state and national levels. Ironically, one year before this incident, the New York State Department of Environmental Conservation (NYSDEC) began formulating a new management plan for black bears in the state. Public risk perceptions associated with black bears and media coverage were considered as part of the initial discussions, and data was collected via a survey of New York residents in March 2002 (Gore 508-509). This initial survey provided an unintended but beneficial representation of resident’s attitudes before the attack that allowed researchers to compare attitudes pre- and post-attack after completing an additional follow up survey three weeks after the infant’s death. Previous studies have shown that wildlife related human fatalities are often widely covered by the media and expose many people to messages about the incidents and animals involved they may not have otherwise had contact with. This was also the case in New York State following the attack; there was increased public awareness due to media coverage (Boyer 513).

An illegally killed bear found outside of the Avoyelles Parish in Louisiana.

An illegally killed bear found outside of the Avoyelles Parish in Louisiana.

However, Boyer et al. found that in this instance there was not much amplification of social risk perception of black bears. Confused by this contradiction to what was predicted by the “social amplification of risk theory”, the researchers looked into potential reasons for the change in perception. They found that many of the articles that discussed the attack were not only short-term coverage, but also emphasized the rarity of such attacks, giving Boyer and his colleagues reason to believe that by media coverage emphasizing the rarity of these attacks, existing perceptions of low risk were reinforced (Boyer 513-514). In this instance, media actually had a positive effect on conservation by overall practicing honest reporting that included most, if not all, of the facts.

It is my personal belief that the media can have a massive impact on the public opinions and perceptions of risk when it comes to conservation, especially when it concerns predatory animals that have historically been involved in attacks and negative interactions with humans. Many times this impact is negative, as was the case for Sonya the slow loris, but it can also be positive, as seen in the aftermath of the black bear attack on the infant in New York. Media has the unique opportunity to bring people into contact with topics or animals they would never normally interact with, and journalists have the opportunity (and arguably a moral responsibility) to use their resources as tools for conservation and not sensation.

 

References

Boyer, Steve. “Sharks and the Media.” For most current information: http://extension. oregonstate. edu/catalog (1987): 119.

Gore, Meredith L., et al. “Effects on risk perception of media coverage of a black bear-related human fatality.” Wildlife Society Bulletin 33.2 (2005): 507-516.

McLeod, J., Ward, S., & Tancill, K. (1965). Alienation and uses of the mass media. The Public Opinion Quarterly, 29(4), 583-594. doi:10.1086/267361

Muter, Bret A., et al. “Australian and US news media portrayal of sharks and their conservation.” Conservation Biology 27.1 (2013): 187-196.

Nekaris, K. Anne-Isola, et al. “Tickled to death: analysing public perceptions of ‘cute’videos of threatened species (slow lorises–Nycticebus spp.) on web 2.0 Sites.” PloS one 8.7 (2013): e69215.

Catalysts Behind the First Shark and Ray Sanctuaries in the Philippines

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Jeff Palumbo, SRC Intern

The Philippines – one of the few places in the world where pelagic thresher shark (Alopias pelagicus) sightings are a common occurrence, happening daily. These rare sharks ritualistically travel to seamounts in order to be cleaned of parasites, all just within reach of scuba divers.  Malapascua, a spit of land less than two miles long boasts the closest proximity to these sunken-island reefs. Due to this unique ecotourism opportunity, the island has exploded in popularity for science and sport. Renowned researchers from all over the globe make their pilgrimage to the Philippines to study this incredible encounter. For its part, Malapascua has responded. It is also home to SharkLink, a locally run ecological safety measure masterminded by DiveLink Cebu. Partnering with dive shops, fisherman, scientists, government bodies and the community, Project SharkLink strives to address and monitor the delicate intricacies and economics of tourism, eco- concerns and the native livelihood – fishing. DiveLink Cebu, also host to the Thresher Shark Research and Conservation Project, collaborates with Save Philippines Seas as well as many other like-minded organizations. These watchdog organizations engage the help of research volunteers and locals alike. Researchers compile data to determine trends in reef health and thresher shark behavior. Patterns are recorded along with local fish catch reported by the native fishermen. Government and community officials evaluate the findings to manage the delicate balance of sport, science, sustainability and economics. Dive Link and its brother organizations are pivotal in analyzing the data and integrating all stakeholders to find feasible solutions, often involving community members and eliciting support from resident businesses.

To get a glimpse of how Project SharkLink was conceived, the article “For the Love of Sharks” by Dennis Bait-tit tells the story of DiveLink Cebu owner Gary Cases, a staunch and vocal advocate for conservation and community involvement for years on Malapascua. Recognizing early on the interplay between the island’s competing concerns, Dennis’s quest for solutions led him to DiveLink where he met Gary and quickly realized they shared the same goals. Over time they constructed a communication medium for those who did not have a voice.  Initiating dialogue with all the necessary parties, Project SharkLink was born:

“a collaborative project that aims to define characteristics of cleaning stations for sharks and rays… as well as, develop a feasibility study of proposed social support programs for the local community on Malapascua Island.”

Thresher sharks are opportunistic hunters and can be easily caught if feeding during the day. (Oliver & Turner et al. 2013) This phenomenon allows poachers easy access to the sharks, and can cause severe decline to populations. The fins are often sold for massive profits in the illegal shark finning trade. Other Illegal fishing practices include: cyanide poisoning, net use and dynamite fishing. Explosions have decimated reefs and cleaning stations throughout the thresher habitat. Malapascua’s ecotourism boom has also increased demand on the local fisheries resulting on the implementation of new laws, thus mounting pressures on the local fishermen and economy. Project SharkLink strives to educate the community to alleviate these transitional dilemmas. They have made significant inroads by implementing, Migo sa Iho, or Friend of Sharks. Migo sa Iho is a group of fishermen who protect the waters they once fished. Due to their hard work and recent successes, the Bureau of Fisheries and Aquatic Resources have deputized the group allowing them to enforce the new laws. Impressed by their progress, Greenpeace Southeast Asia assisted in organizing the first Shark Summit in the Philippines thereby enabling more stakeholders to become involved in the discussions of shark conservation than ever before in the Philippines. Information compiled from SharkLink, Thresher Shark Research Project, Save Philippines Seas and others, was used to help implement the first shark and ray sanctuary in the Philippines. The Shark Summit helped finalize these important new laws. It also increased fishing restrictions on all shark and ray trade throughout the country, not just Malapasqua. The viable and sustainable results on Malapasqua underscore the need for and importance of scientific collaboration and citizen science.

Figure 2. Research divers deploying quadrat for photo capture along the cleaning station. Large teams are used per quadrat, thus impact to the coral surface is minimalized.

Figure 2. Research divers deploying quadrat for photo capture along the cleaning station. Large teams are used per quadrat, thus impact to the coral surface is minimalized.

I met Gary and Dennis when I started working with the Thresher Shark Research and Conservation Project. I was immediately fascinated with how science and politics collided on such a small, remote island far from governmental influence and oversight. As a research diver, I wanted to help collect vital data from this rare ecosystem. Thresher sharks come to shallow-water cleaning stations and exhibit “circular-stance-swimming.” (Simon & Husey et al. 2011) This figure-eight pattern allows prolonged time for cleaner fish to interact with the sharks. Additionally, a deeper understanding of thresher shark behavior and the symbiosis they share with cleaning fish can be ascertained. The cleaning stations found on seamounts or sunken reefs are home to vast coral life. Species of fish that feed off of the parasites on larger fish live here and clean the sharks. (Grutter 1999) Research is leading experts to believe that seamounts are an important ecological habitat for large pelagic species, such as sharks and rays. (Simon et al. 2006 & 2011) Pelagic thresher sharks have low fecundity and mature rates. They are also listed as vulnerable by the International Union for the Conservation of Nature and Natural Resources. Reef monitoring techniques were used to understand how these reefs are being altered over time near Malapascua. I was a part of a team of divers that constructed quadrats. These quadrats were used to measure and take pictures of vital cleaning station habitat. The reef area was split into sections and important information was compiled over a series of dives. Thousands of pictures were analyzed so that percent cover of reef organisms could be recorded.  Therefore, changes to the structure of the cleaning stations sharks preferred could be documented over time. These images were then stitched together to illustrate a detailed aerial view of the study site.

Figure 3. A stitched photomap of the cleaning station surveyed by dive teams working on the Thresher Shark Research and Conservation Program. Maps likes these will be assessed over time and compared to determine site health.

Figure 3. A stitched photomap of the cleaning station surveyed by dive teams working on the Thresher Shark Research and Conservation Program. Maps likes these will be assessed over time and compared to determine site health.

Projects like SharkLink and the Thresher Shark Research Project have produced important data that cannot be ignored and which has led to significant changes instigating new law enforcement. Monitoring initiatives in the area show a heavy decline in reef cover since recent disasters. On top of detrimental fishing practices such as dynamite fishing, the Philippines has been victim to the strongest storm in recent history decimating reefs including those near Malapascua.  Recovery is slow. With each setback, government officials are realizing the importance of the need for stringent laws and improved enforcement to facilitate the healing process after such devastating events coupled with illegal fishing practices. In light of the storm Yolanda, the first shark and ray sanctuary in the Philippines was born. However, how long funding will last and whether or not succeeding government bodies will continue to agree, is unclear. Dennis believes monitoring programs involving citizen science are imperative due to the continuous data they produce at low cost. Money can then be spent in areas where funding may become lacking. At the same time, citizen science efforts spread awareness to local communities and dive operations  allowing them to participate in the process. Initiatives like the Migo sa Iho must also continue to integrate members of the community to help protect marine resources and expand awareness. Community outreach and participation is key to continued agreement to sustainable marine conservation. And, the good news continues, Dennis has recently been informed that thresher sharks will be included in CITES Appendix II!

Works Cited:

Grutter, Alexandra S. “Cleaner fish really do clean.” Nature 398.6729 (1999): 672-673.

Oliver S. P., 2006. The Behaviour of Pelagic Thresher Sharks (Alopias pelagicus) in Relation to Cleaner Fishes (Labroides dimidiatus & Thalassoma lunare) on Monad Shoal, Malapascua Island, Cebu, The Philippines. University of Wales MSc thesis, 2006.

Oliver SP, Hussey NE, Turner JR, Beckett AJ (2011) Oceanic Sharks Clean at Coastal Seamount. PLoS ONE 6(3): e14755. doi:10.1371/journal.pone.0014755

Oliver SP, Turner JR, Gann K, Silvosa M, D’Urban Jackson T (2013) Thresher Sharks Use Tail-Slaps as a Hunting Strategy. PLoS ONE 8(7): e67380. doi:10.1371/journal.pone.0067380

Fishes that rule the world: circumtropical distributions revisited

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By William Evans, SRC Intern

Fishes that rule the world: circumtropical distributions revisited (2015) by Gaither, Bowen, Rocha, and Briggs reviews and updates the list of circumtropical fishes that was published in1960. The term circumtropical is defined by Merriam-Webster dictionary as “surrounding or distributed throughout the tropics”. Circumtropical fishes represent less than 1% of the world’s aquatic vertebrates but are a diverse group that includes common species such as tuna, remoras, sharks and lantern fishes.

Nurse_shark_with_remoras

“Nurse shark with remoras” by Duncan Wright (User:Sabine’s Sunbird) – en: Image:Nurse shark with remoras.jpg. Licensed under CC BY-SA 3.0 via Wikimedia Commons

A majority of these species are pelagic or bathypelagic. Through recent updates in technology and the availability to access information using resources like Fishbase and the Catalogue of Fishes, the list was updated from the original 107 species from 1960 to 284 species. The scientists were not only able to use online resources but also used DNA sequencing technologies to better comprehend specific genetic lineages, opposed to only using morphology. Although morphology is a tool that most scientists use in the field, there is room for error, especially with species with such close lineages like the great hammerhead and the scalloped hammerhead. By using DNA barcoding, they were able to compile a more accurate list of when a previously listed species was actually more than one.

The researchers searched FishBase from June to December of 2014 to primarily analyze the distribution of the 107 fishes on the original list. Species were removed if they were only found in the southern ocean and subtropical convergences. After using FishBase, they used the Shorefishes of the Tropical Eastern Pacific (EP) and other records. From these searches, species listed as “circumglobal” were removed, as well as species that have no present records in the East Pacific. Google Scholar searches were also used to discover genetic information from using simple searches of the species name, common name, followed with “genetic” or “molecular” and the first 50 results were then analyzed. A search in the Barcode of Life Data System (BOLD) was also used to record sequences and bins for each species for further examination. Many of the species added were bathypelagic (73% of the 196 new species added) and 19 taxa were removed from the original list. Some of the organisms had no or limited genetic data, showing that many species have not been assessed using these current genetic coding tools.

There are some challenges that exist when it comes to creating and editing a list as extensive as this one. One is the availability of information. Cryptic species, ones with difficultly-distinguishable features, can be a problem when doing a biodiversity study. Although some cryptic species, like the scalloped hammerhead, have a plethora of genetic data, others do not. Of the current list, 74% of the species do not have genetic data, which means that the list could be more accurate if more data was available.

Scalloped_hammerhead_cocos

“Scalloped hammerhead cocos” by Barry Peters` – 637943300305. Licensed under CC BY 2.0 via Commons

The journal discusses some biological factors that can explain the global distribution of the fishes found on the list. These factors include a vagile adult phase, a long pelagic duration, habitat preference, and old lineages. In addition to biological factors promoting distribution, there are factors that inhibit global distribution. Those mainly include the East Pacific Barrier and the thermal regime. The East Pacific Barrier is defined as a 4000 km to 7000 km region of deep ocean that separates the East Pacific from the Central Pacific which demonstrates the largest divide in circumtropical fauna that inhabit shallower waters. The thermal regime defined as an area off of South Africa with a topographically and hydrologically complex area mainly due to the cooler Benguela Current that moves northward that is deemed lethal to many tropical organisms.

Although the list has been updated to better represent the amount of circumtropical fish species, a majority of the organisms on this list have little to no genetic data, displaying a disconnect in the amount of information that we know. The authors note that as technology advances, more of the ocean is explored, and more studies are done, the list will be modified to thus reflect those changes.

References:

Gaither, M. R., Bowen, B. W., Rocha, L. A. and Briggs, J. C. (2015), Fishes that rule the world: circumtropical distributions revisited. Fish and Fisheries. doi: 10.1111/faf.12136

Portrayal of sustainability principles in the mission statements and on home pages of the world’s largest organizations

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By Dana Tricarico, SRC Intern

The 1992 United Nations Conference on Environment and Development held in Rio de Janeiro showed a wide span global agreement to change attitudes and behavior regarding sustainable development- an increasingly important idea beginning in the 1970’s. Conventions and commissions such as these led to terms like “corporate social responsibility (CSR),” i.e. the concept that companies should take into account not only economic objectives, but also social and environmental objectives. By 2010, all Fortune 500 companies reported on CSR. However, despite the CSR efforts and the growing awareness of sustainable practices, there has been some concern that certain organizations may omit or exaggerate their sustainable practices.

Due to this uncertainty, researchers at Charles Darwin University and the Nature Conservancy in Brisbane Australia conducted a study to see whether the increase in knowledge of concepts related to sustainability have actually increased the extent to which companies promote these concepts. In order to do so, two communication tools were looked at for various organizational types. The first communication tool was company mission statement, showing the core values of organizations. The second communication tool was Internet home pages, which are crucial modern forms of marketing for large companies that represent the goals of that company. More specifically, these researchers compared the wording of their oldest mission statement before 2000 to their newest form in 2014 for 150 organizations.  Non-governmental organizations (NGOs), aid NGOs, government development agencies, resource extraction companies, and retailers were all represented in this study. Each statement was analyzed based on their aspirations of poverty alleviation, biodiversity conservation, sustainable practice, climate-change reduction, and gender equity.

Mission statement scores for each of five aspirations compared between the early mission statement (before 2000) and the recent mission statement observed in 2014. A score of zero means that there was no mention of the aspiration. In contrast, a score of 600 means that that aspiration was the top element in the mission statement. Each group consists of 30 large organizations.

Mission statement scores for each of five aspirations compared between the early mission statement (before 2000) and the recent mission statement observed in 2014. A score of zero means that there was no mention of the aspiration. In contrast, a score of 600 means that that aspiration was the top element in the mission statement. Each group consists of 30 large organizations.

After comparing the mission statements for each company, the research team found that organizations differed significantly in the importance of each aspiration. There was a shift towards sustainable ideals in mission statements for some of the five industry sectors, most notably seen in the resource extraction companies. The comparison of the 2014 web home pages showed that conservation NGOs favored wildlife in their aspirations as an organization, and aid NGOs focused more on poor communities and the empowerment of women. It also seemed as though mining companies were proud of their environmental record based on the fact that many of their websites portrayed the need for an increased awareness in sustainable concepts.

The percentage of company home web pages depicting an awareness for poverty alleviation, biodiversity conservation, sustainable practice, responding to climate change and gender equity. Each group consists of 30 large organizations.

The percentage of company home web pages depicting an awareness for poverty alleviation, biodiversity conservation, sustainable practice, responding to climate change and gender equity. Each group consists of 30 large organizations.

However, despite some positive changes between mission statements and home pages, there were many issues associated with the findings. The first issue is that there was little change over time despite the large increase in sustainability knowledge since the 1970’s. Another issue proved that while many companies value sustainable ideals, there was little mention as to how they planned to achieve those ideals, especially when it came to climate change.

The conclusions from this research are useful because it shows that these companies need to measure their commitment to sustainability principles in a different form than the CSR reports in order to better hold themselves accountable to their ideals. Additionally, the results show that there still needs to be a greater emphasis on sustainability principles in the core values of major companies. Due to the influence of large companies, this shift could help influence stakeholders and the general public to change their sustainability practices in the future.

 

Outside Source Used:

Garnett, S. T., Lawes, M. J., James, R., Bigland, K., & Zander, K. K. (2015). Portrayal of sustainability principles in the mission statements and on home pages of the world’s largest organizations. Conservation Biology.

 

Buoyless Nets Reduce Sea Turtle Bycatch in Coastal Net Fisheries

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By Ryan Keller, SRC Intern

Bycatch of megafauna (larger organisms) is a serious negative side effect that stems from the practice of commercial fishing worldwide. Often fishing practices such as long lines or using nets are effective at catching the target species but also will entrap many other organisms. Often for organisms that breath air this means mortality as they may be stuck underwater for a longer period of time then they able to hold their breath.  Baja California Sur, Mexico has some of the highest recorded megafauna bycatch rates of anywhere in the world due to heavy use of bottom-set nets. Unfortunately this area also happens to be a foraging mecca for endangered loggerhead turtles.

Pictured above: An endangered loggerhead turtle swimming over a reef. Loggerheads when caught in nets cannot get to the surface to breathe leading to death.

Pictured above: An endangered loggerhead turtle swimming over a reef. Loggerheads when caught in nets cannot get to the surface to breathe leading to death. https://commons.wikimedia.org/wiki/File:Loggerhead_turtle.jpg

Between 2007-2009 Stanford University researches worked with local fisherman to compare the megafauna’ bycatch rates between traditional nets (with buoys) and bouyless nets.  Both types of nets were set near each other during the trials and the difference in bycatch recorded. The nets were checked on a regular basis to try and prevent mortality of any turtles caught in the nets. Local fisherman were compensated for setting two of the experimental nets and having a researcher with them on their trips. Later in the experiment partner fisherman were hired to fish exclusively the bouyless nets. All turtles that were caught in the nets were tagged, measured and released.  In all trials the fisherman were allowed to keep their catch and bring it to market.  The difference in the monetary value of catches between types of nets was also calculated.

As seen above: A green sea turtle (Chelonia mydas) stuck in a fishing net. Turtles often get stuck in nets that have broken free and are floating in the currents throughout the ocean, these nets are termed “Ghost nets”.

As seen above: A green sea turtle (Chelonia mydas) stuck in a fishing net. Turtles often get stuck in nets that have broken free and are floating in the currents throughout the ocean, these nets are termed “Ghost nets”. https://commons.wikimedia.org/wiki/File:Sea_turtle_entangled_in_a_ghost_net.jpg

There was found to be a 67% mean reduction in the number of turtles caught in the bouyless nets compared to traditional nets with a minimal impact on the quantity of target species. There was a decreased market value in the catch from the bouyless nets but this is most likely due to higher than average amounts of certain species being caught and brought to market at one time driving the price down. There has been other research done in this area that shows small changes such as illuminating nets at night also reduce the amount of bycatch. It is not practical to just ban the present commercial fishing methods completely. Finding ways to make small changes that have minimal impact on the fisherman and their income while drastically decreasing bycatch is the best way to gain acceptance and support from the industry. If the fisherman are minimally impacted they are much more likely to take up the new practices and not resist or revert back to prior methods.

 

Peckham, S. H., Lucero‐Romero, J., Maldonado‐Díaz, D., Rodríguez‐Sánchez, A., Senko, J., Wojakowski, M., & Gaos, A. (2015). Buoyless Nets Reduce Sea Turtle Bycatch in Coastal Net Fisheries. Conservation Letters.