Effects of fishing rope strength on the severity of large whale entanglements

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By Leila AtallahBenson, SRC Intern

 

Figure 1. A free swimming humpback whale, that managed to avoid fishing gear entanglements.

Figure 1. A free swimming humpback whale, that managed to avoid fishing gear entanglements.

On top of whales being majestic giants that are exciting to watch, they are also an important animal for marine ecosystems. They enhance primary productivity in nutrient lacking areas and ocean surfaces, and their carcasses provide habitat and energy sources for deep-sea species1. In both these instances, whales fix carbon, turning inorganic carbon to organic compounds. This not only makes more room for carbon to be absorbed, helping with global warming, but contributes to the available amount of organic matter that marine organisms utilize. Whales are also important to the economy, drawing in around $2 billion per year through whale-watching businesses2.

Unfortunately, these species are prone to human fishing gear entanglements, since they are so large and often spend time in prime fishing areas. Once a whale is entangled the individual can drown quickly, or may be able to breath but later dies from starvation, injuries endured by the fishing gear, increased energetic demands, or stress3. These entanglements often come from pot/trap and gillnet fisheries4. Protecting these species not only helps whales, but helps protect our oceans and economy.

Between 1994 and 2010, Knowlton et al. explored the breaking strength of 132 fishing ropes that were found on 70 whales. This included 30 right, 30 humpback, 2 fin, and 8 minke whales, all along the east coast of the United States. In the U.S., fin and humpback whales are protected, and both in the US and Canada, right whales are protected by law. All of the whales that rope was collected from were categorized by species. Right and humpback whales were also separated by age group. The severity, configuration, and any injuries of the entanglement were recorded with pictures.

Most of the gear sampled was retrieved by the Atlantic Large Whale Disentanglement Network. The entangled rope strength was determined. The majority of entangled rope was found to be in good or very good condition. The rope material, its diameter, breaking strength, condition, and how many of that rope found were considered (table 1).

AtallahBenson_Table 1

The authors asked a few questions from this information. One question was if injury severity is related to rope strength? For right whales this proved to be true. With increased rope strength, right whales had more severe injuries. However, this was not true for humpback whales, whose injuries did not get worse with rope strength, but their injuries seemed to be more randomized.

Another important question asked was if rope strength correlated with whale species or age (see figure 2)? Some of these correlations were clear to see in the evidence. Both right and humpback whales were found with ropes of higher breaking strength than minke whales. Adult right whales were found in significantly stronger rope than juvenile right whales, and both adult and juvenile humpback whales. The average breaking strength was 19.30 kilonewton (nK) for right whales, 17.13 kN for humpback whales, and 10.47 kN for minke whales. The 2 fin whale ropes were 11.12 and 31.14 kN.

AtallahBenson_Figure 2

This information helps us take a better look at the fishing gear we use now, and allows us to make changes to better protect these magnificent creatures. There were only limited numbers of whales that were entangled in rope strengths below 7.65 kN. The use of special ropes, called reduced breaking strength (RBS) ropes, of 7.65 kN or less could reduce whale entanglements at least by 72%. Fisherman in the study area haul about 2.24-3.11 kN for lobster, 2.45-3.11 for stationary gillnets, and at most 6.38 nK for dragging gillnets. These RBS ropes of 7.65 would work for these normal fishing endeavors, and save the whales at the same time. So the next time you’re going out fishing, be sure to grab some RBS rope and help save the whales!

References

Knowlton AR, Robbins J, Landry S, McKenna HA, Kraus SD, Werner TB. 2015. Effects of fishing rope strength on the severity of large whale entanglements. Conservation Biology: 1-11.

1 Roman J, Estes JA, Morissette L, Smith C, Costa D, McCarthy J, Nation JB, Nicol S, Pershing A, Smetacek V. 2014. Whales as marine ecosys- tem engineers. Frontiers in Ecology and the Environment 12:377– 385.

2 O’Connor S, Campbell R, Cortez H, Knowles T. 2009. Whale Watching Worldwide: tourism numbers, expenditures and expanding economic benefits, a special report from the International Fund for Animal Welfare, Yarmouth MA, USA.

3 Moore MJ, van der Hoop J, Barco SG, Costidis AM, Gulland FM, Jepson PD, Moore KT, Raverty S, McLellan WA, editors. 2013. Cri- teria and case definitions for serious injury and death of pinnipeds and cetaceans caused by anthropogenic trauma. Diseases of Aquatic Organisms 103:229–264.

3 Cassoff RM, Moore KM, McLellan WA, Barco SG, Rotstein DS, Moore MJ. 2011. Lethal entanglement in baleen whales. Diseases of Aquatic Organisms 96:175–185.

3 Pettis HM, Rolland RM, Hamilton PK, Knowlton AR, Kraus SD. 2004. Visual health assessment of North Atlantic right whales Eubal- aena glacialis using photographs. Canadian Journal of Zoology 82: 8–19.

4 Johnson A, Salvador G, Kenney J, Robbins J, Kraus S, Landry S, Clapham P. 2005. Fishing gear involved in entanglements of right and hump- back whales. Marine Mammal Science 21:635–645.

The Effect of Materialism on Ecotourism Attitudes, Interest, and Intention

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By Dana Tricarico, SRC Intern

The term “ecotourism” has been widely used since the late 1980s and has become a major niche in not only the tourism sector itself, but also in tourism studies (Weaver and Lawton, 2007). Traditional approaches to conserving biodiversity in ecologically important areas have proved to be ineffective due to conflicts between park authorities implementing conservation laws and the local people to those protected areas. Ecotourism has provided a solution to this problem by combining protection of areas with cooperation from the local people so that these people feel empowered and a part of the management decisions (Lai and Nepal, 2006). Despite the positives of this form of tourism, especially in places like small island destinations, which are known for their unique cultures and remoteness, there are still challenges with implementing this replacement to mass tourism. First and foremost, local authorities need to not only see the potential for tourism in these particular locations, but they must provide strong leadership to maintain the community’s engagement and continue to empower the local people. Many governments feel pressured to join the pattern of traditional mass tourism by building large resorts which causes them to lose sight of how rewarding it can be to have sustainable forms of tourism instead (D’Hauteserre, 2015). Researchers Allan Cheng Chieh Lu et. al (2014) decided to look at ecotourism from a different angle.  Rather than the implementation, they investigated the traveler aspect of ecotourism.

A native of French Polynesia demonstrates sustainable tourism by leaving a low environmental footprint when making cloths and souvenirs with strips of tapa. (Hauteserre)

A native of French Polynesia demonstrates sustainable tourism by leaving a low environmental footprint when making cloths and souvenirs with strips of tapa. (Hauteserre)

This particular study looked at how materialism influences ecotourism attitude, ecotourism interest, ecotourism intention as well as the willingness to pay a premium for ecotourism. In order to capitalize on the values that ecotourism promotes and to try and fix the issues associated with it, this type of research is important to see the values that may influence travelers and their opinions about taking part in ecotourism. Materialism, i.e., the emphasis people place on the satisfaction of life from their possession of material goods, is very prominent in the western society and has been increasing for decades. Therefore, this thought process is important in tourism studies because it can conflict with environmental conservation, a major component of ecotourism. This is because environmental conservation often goes hand in hand with decreasing overconsumption and recycling old goods.

The beginning stages of this research entailed a literature review, which was done to create hypotheses based on prior research. After doing so, a conceptual framework was created to show their findings. The study itself was done by collecting data from 2,352 Italian travelers using an online self-administrated questionnaire. The survey had seven sections, six of which measured different concepts with the seventh measuring the demographics of the respondents. To measure ecotourism interest, ecotourism attitude, and willingness to pay a premium, the respondents were given statements related to each of those topics being measured and then asked to rank them. This scale was from 1-7 with 1 representing that statement was not important to them, and 7 representing that it was very important to them. To interpret the results, statistics were used using the Statistical Package for Social Sciences (SPSS).

Photo 2: Conceptual framework for the study by Lu et. al which organizes determinants of ecotourism behavior into five categories. This was created by putting together literature reviews and creating nine hypotheses based on this framework (Lu)

Conceptual framework for the study by Lu et. al which organizes determinants of ecotourism behavior into five categories. This was created by putting together literature reviews and creating nine hypotheses based on this framework (Lu)

The results showed that high value for materialism can negatively influence ecotourism attitude, ecotourism interest, and willingness to pay a premium for eco-tourism products. This is in line with previous research done by Porritt (1984) which explained that a great deal of the issues involved with the global environmental decline is because of materialism. The findings also concluded that, due to the cognitive dissonance associated with having a high desire for material possessions but also wanting to help with environmental issues through eco-tourism, may result in eco-tourism appearing as an unattractive type of leisure.

The conclusions from this study provide practical implications for ecotourism operators as it highlights the necessity to use forms of communication to increase the amount of positive attitudes toward ecotourism. A movement must first garner substantial support before it can truly make an impact, however. For example, ecotourism operations and service providers would need to emphasize the importance of preserving the environment and culture within specific regions through events, media outlets, and advertisement, while at the same time demonstrating the benefits to the local community and the individuals visiting the community (Lu, 2015).  There are many challenges that affect the success of not only implementing ecotourism, but also to catering to the tourists who are highly materialistic. With extensive long-term commitment to educating highly materialistic people about the importance of preserving the environment, however, ecotourism can prove to be extremely beneficial for visitors, locals, and the environment alike.

 

Works Cited

Porritt, J. (1984). Seeing Green: The Politics of Ecology Explained. New York: Blackwell.

Weaver, D. B., and L. J. Lawton. (2007). “Twenty Years on: The State of Contemporary Ecotourism Research.” Tourism Management, 28 (5): 1168-79.

Dhauteserre, A.-M. “Ecotourism an Option in Small Island Destinations?” Tourism and Hospitality Research 16.1 (2015): 72-87. Web.

Lu, A. C. C., D. Gursoy, and G. Del Chiappa. “The Influence of Materialism on Ecotourism Attitudes and Behaviors.” Journal of Travel Research 55.2 (2014): 176-89. Web.

Lai, Po-Hsin, and Sanjay K. Nepal. “Local Perspectives of Ecotourism Development in Tawushan Nature Reserve, Taiwan.” Tourism Management 27.6 (2006): 1117-129. Web.

 

Addressing knowledge gaps to utilize best practice management for bottom-trawling fisheries

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By Grace Roskar, SRC Intern

Bottom-trawls are a type of fishing gear that can be destructive towards the seabed and its associated organisms. A fishing vessel tows large trawl nets that trap marine animals as they are dragged across the ocean floor. With heavy ropes, chains, or bars, the fishing gear disturbs the seabed while capturing nearly anything in its path. About 20% of fish and shellfish caught globally every year are caught using bottom-trawls, amounting to about sixteen million tons.

A typical bottom trawl. Source: https://commons.wikimedia.org/wiki/File%3ABenthictrawl.jpg

A typical bottom trawl. Source: https://commons.wikimedia.org/wiki/File%3ABenthictrawl.jpg

A meta-analysis by McConnaughey et al., in 2005 has shown that bottom trawling for benthic invertebrates may cause reductions in a decrease in biomass, the diversity of fish, and the body size of fish, among other ecological traits of fish communities. Some fish species use specific habitats for shelter or food, and it may be possible that trawling and dredging impact the productivity of these fish species. This is especially important to examine because wild-capture fisheries provide a substantial amount of food for the growing global population.

This study aimed to identify specific questions about bottom-trawling fisheries that key stakeholders feel need to be scrutinized in order to guide suitable policy and management measures. The research also sought out important gaps in global knowledge that, if taken into consideration, would help the advancement of best practice management for bottom-trawling fisheries, defined as ‘bottom trawling that would achieve sustainable fisheries production while minimizing adverse impacts on the environment’ (Kaiser et al 2015).

First, a group of 52 stakeholders from 11 different countries was selected. Stakeholders were categorized either as research scientists or practitioners, a group that comprised of people from fishing and processing industries, non-governmental organizations, or governmental organizations. The stakeholders composed a comprehensive list of ‘knowledge-needs’, which were then voted on and ranked in terms of priority. The underlying idea was that addressing these knowledge-needs would be necessary to support the development of best practice management. Through a one-day workshop, including discussion sessions and voting, a list of 25 top-priority knowledge-needs were finalized out of the original 108.

This flow diagram shows the methods of prioritizing knowledge-needs into a final list.

This flow diagram shows the methods of prioritizing knowledge-needs into a final list.

Several statistical tests were used to examine how the reasoning behind the rankings varied between practitioners and scientists. The median scores were positively correlated for each knowledge-need, showing high agreement levels between the scientists and practitioners of what was top priority. Knowledge-needs were organized into categories: direct effects, ecosystem and production, operational, and management and indicators. The management and indicators category was the most represented, with six knowledge-needs in the top ten. The highest-ranked knowledge need was ‘What is the extent and distribution of different seabed habitat types?’ Given the wide range of different stakeholders consulted, the agreement between the scientists and practitioners about the importance of this knowledge-need is encouraging. It shows the pressing need to better understand the relationship between bottom-trawling and the different habitat types affected. Furthermore, six other knowledge-needs were related to some extent to improving knowledge of the impacts of interactions between fishing gear and the seabed. The second most highly ranked question asked, ‘What level of trawl fishing impact on other ecosystem services is acceptable such that sustainable seafood production can be maintained?’ This question suggests that the environmental impacts of bottom trawling, such as changes in ecosystem structure and the fish population, need to be evaluated in comparison to the social and economic impacts of trawling.

A list of the top ten knowledge-needs, including what category each was placed in.

A list of the top ten knowledge-needs, including what category each was placed in.

The rest of the knowledge-needs addressed a range of topics, from the need for better understanding of where bottom trawling occurs and how much of it, to evaluating the ability of certain habitats to recover from the effects of trawling. Many knowledge-needs were additive, such that addressing one would help advancement to another. The study successfully identified specific questions that will be collaboratively discussed further to close knowledge gaps in the global fisheries industry. Future research would include continuing to examine collective knowledge and to use discussion to work towards closing knowledge gaps.

 

References: 

Kaiser, M. J., et al. (2015). “Prioritization of knowledge-needs to achieve best practices    for bottom trawling in relation to seabed habitats.” Fish and Fisheries.      doi: 10.1111/faf.12134

McConnaughey, R. A., and Syrjala, S. E. Short-term effects of bottom trawling and a storm event on soft-bottom benthos in the eastern Bering Sea. – ICES Journal of            Marine Science, 71: 2469–2483.

Percentage of Seabird Species Ingesting Plastic Expected to Reach 99 Percent by 2050

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By Laura Vander Meiden, SRC Intern

A recent study has found that if current rates of plastic introduction into the ocean continue, by 2050 approximately 99 percent of all seabird species will have ingested plastic. The study, published in September of 2015, uses a computer model based upon an analysis of data provided by past plastic-ingestion studies to come to these conclusions.

Unaltered remains of an albatross chick at Midway Atoll. Photo by Chris Jordan of the US Fish and Wildlife Service.

Unaltered remains of an albatross chick at Midway Atoll. Photo by Chris Jordan of the US Fish and Wildlife Service.

Plastic debris harms seabirds and other marine organisms through both entanglement and consumption. Entangled birds can lose motor abilities reducing their ability to feed and fly. Consumption of plastic can lead to pieces accumulating in the digestive system, taking up gut space typically available for food. This negatively impacts an individual’s body condition and severely reduces its ability to care for itself. In some cases, the plastic completely blocks the digestive system, leading to death. Additionally, plastics in the ocean absorb harmful chemicals that can leach out and cause damage to a seabird’s internal organs. Since approximately half of all sea bird species are in decline, these deleterious effects of plastic debris on seabirds are very concerning.

An analysis of data published in studies from 1962 to 2012 shows that 59 percent of the seabird species studied had been found to ingest plastic. Likewise, researchers found that 29 percent of the individual birds sampled in each study contained plastic in their digestive systems. Trends in this data show an average increase of 1.7 percent a year in the proportion of individuals studied that had ingested plastic. To put this in perspective, if that trend continued and those studies were to be redone today, plastic would be found in over 90% of the individual birds sampled.

Using this data, researchers created a computer model to determine areas of risk for seabird species worldwide. The model included 186 species of sea birds. Surprisingly the location of highest estimated impact was not in the Pacific Ocean, home of the infamous Great Pacific Garbage Patch, but at the boundary of the Southern Ocean between New Zealand and Australia. Though concentrations of plastic debris here are lower than other sites, this area is home to a large number of seabird species that are prone to plastic ingestion. This increases the area’s risk above those of locations with higher plastic concentrations.

plastic figure 2

It is important to remember that seabirds are not the only marine organisms affected by plastic debris. An assessment conducted by the United Nations Convention on Biological Diversity found that in 2012, 663 species were affected by marine waste, with 80 percent of the impact coming from plastic marine waste. This is up 40 percent from a previous assessment completed in 1997. Half of all marine mammal species, every species of sea turtle, and one fifth of seabird species were reported to be affected. Fifteen percent of these species are on the International Union for Conservation of Nature (IUCN) Red List, meaning they are at risk of extinction. Species of highest concern include the Hawaiian monk seal, loggerhead sea turtle, and white-chinned petrel.

The seabird study states that ingestion rates rise with increased exposure to plastic. Therefore, if the introduction of plastic into the marine ecosystem was reduced, the study’s projection that by 2050, 99 percent of seabird species will be ingesting plastic could possibly be avoided. Unfortunately, the problem will only continue to get worse unless waste management practices improve and plastic production is reduced. Commercial plastic production first began in the 1950s, over 60 years ago. If current rates of production continue, during the next 11 years we will produce the same amount of plastic as has been created since plastic production first started. Because plastic doesn’t easily biodegrade, this will effectively double the amount of plastic found on Earth.

The United Nations proposed several actions to begin to alleviate this problem. The proposed actions include reduction in the use of plastic as a packaging material, increased producer responsibility, and improved consumer awareness. These solutions are in contrast to past proposals that have only focused on waste management. However in order for a serious impact to occur, change will likely have to take place at international, national and local levels.

Works Cited

Wilcox, C., Van Sebille, E., & Hardesty, B. D. (2015). Threat of plastic pollution to seabirds is global, pervasive, and increasing. Proceedings of the National Academy of Sciences, 112(38), 11899-11904.

Secretariat of the Convention on Biological Diversity and the Scientific and Technical Advisory Panel—GEF (2012). Impacts of Marine Debris on Biodiversity: Current Status and Potential Solutions, Montreal, Technical Series No. 67.

Ecological Impacts of Indiscriminate Fisheries

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By Hannah Calich, SRC Graduate Student

When people think of fisheries they tend to think of species-selective fisheries, such as swordfish or tuna fisheries. However, many fisheries do not focus on a particular species and will harvest most of the fish they catch; these are known as indiscriminate fisheries (McCann et al., 2016). While indiscriminate fisheries can be found globally, they are particularly common in developing countries where fish are the primary source of protein. Understanding the ecological impacts of these fisheries is difficult due to the complex food web interactions that occur when multiple species and sizes are harvested at the same time. In order to understand how susceptible these fisheries are to human activities, methods must be developed to model these complex interactions.

To better understand the ecological impacts of indiscriminate fisheries, McCann et al. (2016) developed food web models to predict how ecosystems may respond to different types of fishing pressure. The authors compared indiscriminate fisheries to trophically selective fisheries, which only target species within a tropic level (e.g., consumers) and selective fisheries, which only target specific species (e.g., snapper; Figure 1). With these models the authors were able to develop a set of rules to predict how ecosystems may respond to different types of fishing pressure.

Figure 1. The three fishing strategies examined in this study are indiscriminate (left), trophically selective (middle), and selective (right). The symbols R, C, P and F stand for resources (e.g., seagrass), consumers (e.g., parrotfish), predators (e.g., sharks) and fishing mortality, respectively.

Figure 1. The three fishing strategies examined in this study are indiscriminate (left), trophically selective (middle), and selective (right). The symbols R, C, P and F stand for resources (e.g., seagrass), consumers (e.g., parrotfish), predators (e.g., sharks) and fishing mortality, respectively.

McCann et al. (2016) created three rules to predict how ecosystems may respond to indiscriminate fisheries.

Rule 1. Fishing down the food web.

In indiscriminate and trophically selective fisheries, top predators are removed from the ecosystem through direct harvest or a decrease in prey availability (i.e., if too many prey species are harvested the top predators may starve).

Rule 2. Fishing across food webs.

High fishing pressure within a trophic level results in fast-growing species becoming dominant. When fast-growing species no longer have to compete with slow-growing species for resources they can quickly increase in numbers.

Rule 3. Fishing down and across food webs.

When indiscriminate fisheries fish down and across food webs, top predators are removed and slow-growing species are replaced with fast-growing species. While an increase in fast-growing fish increases system production, it also decreases community-level stability due to a decrease in diversity.

 

Figure 2. Map of Tonlé Sap, Cambodia. Photo by: Matti Kummu/Wikimedia Commons.

Figure 2. Map of Tonlé Sap, Cambodia.
Photo by: Matti Kummu/Wikimedia Commons.

To determine if these rules can be applied to a real-life scenario, McCann et al. (2016) examined the Tonlé Sap ecosystem in Cambodia, which has a highly productive indiscriminate fishery (Figure 2). Tonlé Sap has experienced a steady increase in fishing intensity over time, which has resulted in a loss of top predators. The authors determined that the mean size of the species “at risk” within the ecosystem was nearly twice that of the species “of least concern” (i.e., the faster growing, smaller-bodied species have more stable populations). Consistent with the author’s predictions, this ecosystem appears to have lost top predators and slow-growing consumers but is still productive due to an increase in small, fast-growing species.

Overall, indiscriminate fishing reduces the abundance of top predators, depletes slow-growing species, and increases the number of fast-growing species while reducing ecosystem diversity. These shifts can leave ecosystems vulnerable to changing environmental conditions such as climate change or hydroelectric development. This study emphasizes the importance of incorporating ecosystem structure into fisheries management because trends in species abundance may be misinterpreted if an ecosystem is not well understood (e.g., an increase in fast-growing fish abundance may be interpreted as a positive change when it may actually indicate a decrease in ecosystem diversity and stability).

 

Reference:

McCann K.S., Gellner, G., McMeans, B.C., Deenik, T., Holtgrieve, G., Rooney, N., Hannah, L., Cooperman, M., Nam, S. (2016). Food webs and the sustainability of indiscriminate fisheries. Canadian Journal of Fisheries and Aquatic Science. 73:1-10.

Marine Reserves Still Beneficial for Conservation Near Coastal Rivers and Cities

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By Kevin Reagan, SRC Intern

As the ocean becomes more of a “hot topic” in the media and public forums, planners and designers of marine reserves must increasingly factor in socio-economic factors alongside biological principles when discussing policy. The human aspect that is usually responsible for the initial need for conservation and things like no-take marine reserves is undeniable, and as populations continue to increase, the negative impact many human activities have on marine environments does as well. These effects are particularly strong in coastal cities or estuarine flows, where a river flows into the ocean. However, this may not necessarily mean that marine reserves would not be beneficial in these areas though. In his 2015 study, Chantal M. Huijbers and colleagues analyzed whether being located close to major influences like cities on the coast affected the efficacy of marine reserves in enhancing the number of organisms that were present, relative to other areas outside of the reserve.

Diagram representing the 3 major categories of determinants expected to influence the performance of marine reserves.

Diagram representing the 3 major categories of determinants expected to influence the performance of marine reserves.

Marine reserves are usually placed in deeper, offshore locations that have little to no commercial value. These areas are generally remote, and partly chosen because they offer the least chance of the reserve interfering with human activities such as fishing. Though this leaves areas near coastal cities poorly protected, these decisions are made because of impacts like habitat degradation and fishery overexploitation that occur in coastal areas that increase pressure on marine ecosystems. Native marine diversity has been shown to decrease with increasing human population density, and coastal areas generally have greater levels of biodiversity than offshore areas; marine reserves can play a crucial role in protecting this diversity, but both positive and negative impacts have been seen. There is, though, a chance that the extent of positive effects from things like fishing restraints is overshadowed by negative effects from sources outside of the boundary of the reserve.

Edgar et al. demonstrated that for a marine reserve to be effective, it must be four out of these five things:

  • No-take zone
  • Large
  • Have high levels of compliance with regulations,
  • Have been protected for a long period of time
  • Separated from fished areas by geographic boundaries or channels

These factors demonstrate the importance of human-related factors in planning future marine reserves, and intuitively it would seem that the best framework for planning marine reserves is the current one that delegates them to remote offshore locations. But, after compiling a database of peer-reviewed studies that reported the biological effects of marine reserves and examining 150 articles published between 1977-2012 and included 113 different reserves, Huijbers found that there was a greater abundance of organisms in marine reserves compared to control areas regardless of the reserves proximity to coastal influence. Essentially, the reserves close to urban centers were indistinguishable from those that were more remote.

Example of what a healthy, protected reef can look like. Flynn’s Reef, Phillips Island, Australia, part of the Great Barrier Reef Marine Park.

Example of what a healthy, protected reef can look like. Flynn’s Reef, Phillips Island, Australia, part of the Great Barrier Reef Marine Park.

Huijber et al. only included studies that measure fish, invertebrate, and algal abundance in formally designated reserves that were also fully protect no-take areas, and each study included one or multiple sites that were both in and outside the reserve, or before/after the reserve was established. After using statistical analysis to examine the relationship between eleven predictor variables that measure the effect of coastal influence and marine reserves, they showed that coastal marine reserves were equally as effective as less-developed offshore locations. Though variations in the methodologies of the studies included in the analysis may affect the strength of the findings, the data examined and presented is compelling and at the very least warrants further research on the subject.

For any of these policies to work, efficient enforcement of rules and regulations is paramount. Planners cannot assume that people will comply with regulations out of the goodness of their hearts. Enforcement is key and studies have shown that there is a greater effect of reserves on ecosystem health and biomass where there is less encroachment. That being said, placing marine reserves near coastal areas will also raise awareness of biodiversity and can potentially increase the success of marine reserves. Coastal marine reserves can provide the crucial link between the social and ecological environments in these areas and end up fostering a sense of admiration and appreciation for what the ocean has to offer for generations to come.

 

Huijbers, Chantal M., et al. “Conservation benefits of marine reserves are undiminished near coastal rivers and cities.” Conservation Letters (2014).

Implications of climate change for the sex ratios of sea turtle hatchlings

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By Grace Roskar, SRC Intern

Sea turtles have existed on Earth for over 100 million years and presently inhabit warm waters in tropical and subtropical latitudes. The International Union for the Conservation of Nature has classified six of the seven species of sea turtles as critically endangered, endangered or vulnerable (IUCN, 2014 in Laloë et al., 2016). Threats to sea turtles include being taken as bycatch from fishing, poaching of eggs, and destruction of their habitats on land or at sea. Moreover, all sea turtle species come ashore to lay their eggs on sandy beaches, but these critical habitats face changes in air, water, and sand temperatures and rising sea levels (Santos et al., 2015). These climatic impacts occur at varying timescales and in different geographic locations, which makes it more challenging to respond to and mitigate these various threats (Fuentes and Cinner, 2010).

Like many reptiles, sea turtles possess temperature-dependent sex determination (TSD), which means that the incubation temperature of eggs in the nest determines the sex of an individual. Each species has a certain threshold, or pivotal, temperature, where equal numbers of males and females are produced. Temperatures below this pivotal temperature produce males whiles temperatures above produce females (Standora and Spotila, 1985). The determination of sex occurs in the middle third timeframe of the development of the embryo (Tapilatu and Ballamu, 2015). Due to TSD, increasing temperatures are a concern to sea turtles and were recently determined to be one of the largest threats to sea turtle populations (Fuentes and Cinner, 2010). Sex ratios could become skewed, and in more extreme cases, local extinctions could occur (Janzen, 1994 in Laloë et al., 2016). Warmer nest temperatures may lead to a greater majority of female hatchlings (Howard, Bell and Pike, 2015). Determining what ways increasing temperatures can impact populations is a priority for the conservation of sea turtles (Laloë et al., 2016).

In one study, Fuentes and Cinner (2010) used the knowledge of sea turtle experts to estimate how increasing temperatures and other climatic processes will impact sea turtles’ reproductive phases. The turtles of interest were green turtle (Chelonia mydas) populations in the northern Great Barrier Reef of Australia. Twenty-two scientists and managers were surveyed, and both groups agreed that higher sand temperatures could be considered the biggest threat to the reproductive output of these populations. The experts believe that higher sand temperatures will cause “two times more impact to sea turtles’ reproductive output than sea level rise and three times more impacts than altered cyclonic activity” (Fuentes and Cinner, 2010).

However, studies have also showed certain levels of resilience in some sea turtle populations. Howard, Bell, and Pike (2015) studied flatback sea turtles (Natator depressus) that are only native to Australia. Eggs were incubated in a laboratory to examine if the population was vulnerable to higher temperatures while nesting. The eggs were collected from beaches in northeastern Australia, and thus their pivotal temperatures were compared to those of populations from more temperate latitudes in Australia. It was found that the embryos in their study were resilient to incubation at high temperature, able to withstand temperatures almost 4°C above those from more southern populations. Moreover, the pivotal sex-determining temperature was different from past studies. It was previously thought that 29.5°C would produce an equal sex ratio, but for the eggs in this study, 30.4°C was the pivotal temperature. With a higher pivotal temperature, increasing environmental temperatures could drive the sex ratios closer towards equality. Therefore, even under extreme climate change scenarios, this high pivotal temperature adaptation may allow some flatback turtle populations to still produce more equal sex ratios (Howard, Bell, and Pike, 2015).

Not all sea turtle populations have shown such resilience. Fuentes, Hamann, and Limpus (2010) studied sand and air temperatures in the northern Great Barrier Reef. By using models and projections, it was estimated that by 2030, the sex ratios of hatchlings will be greatly skewed towards females. This has also been predicted for other nesting sites such as Cape Canaveral, Florida, and Bald Head Island, North Carolina (Hawkes et al 2007 in Fuentes, Hamann, and Limpus 2010). Laloë et al. (2016) examined historical data for incubation temperatures and sex ratios for green, hawksbill (Eretmochelys imbricata), and leatherback (Dermochelys coriacea) turtles nesting in St. Eustatius in the northeastern Caribbean. Their analysis suggested sex ratios have been skewed towards females for decades, and climate change will only intensify this. It was projected that in St. Eustatius “only 2.4% of green turtle hatchlings will be males by 2030, 1.0% by 2060, and 0.4% by 2090,” (Laloë et al., 2016). Sex ratios dominated by females have already been reported at nesting sites around the world (e.g. Barbados, Cyprus) and at certain sites, some ratios are as high as 100% female (Binckley et al., 1998 in Laloë et al., 2016).

Projections of increasing incubation temperatures at one site in St. Eustatius. Graph A shows projections for 2030, graph B shows 2060, and graph C shows 2090 (Laloë et al., 2016).

Projections of increasing incubation temperatures at one site in St. Eustatius. Graph A shows projections for 2030, graph B shows 2060, and graph C shows 2090 (Laloë et al., 2016).

Sea turtles have existed for millions of years and have previously shown the ability to adapt during periods of sea level rise and temperature changes, such as changing nesting site locations or utilizing new migratory paths (Fuentes, Hamman, and Limpus 2010). However, modern-day changes in climate have been predicted to occur at a much faster timescale than past changes. Therefore, the capabilities of sea turtles adapting to these changes are still fairly unknown (Fuentes, Hamman, and Limpus 2010). There are several management options that have been suggested in order to mitigate the effects of higher temperatures. Some active methods include artificially changing the sand temperature by sprinkling cool water on the sand, covering areas of the beach with vegetation, or creating artificial shade (Naro-Maciel et al., 1999 in Fuentes, Hamman, and Limpus 2010). Other methods include the use of hatcheries and artificial incubation where temperatures can be controlled, but there is still uncertainty about the risks associated with changing natural sex ratios. Management could also be aimed at population-wide measures, including protecting key habitats, reducing bycatch of sea turtles, and preventing illegal harvest (Fuentes and Cinner, 2010).

 

A table outlining possible management measures to reduce climate change impacts on sea turtle reproduction, provided by experts surveyed in the study by Fuentes and Cinner (2010).

A table outlining possible management measures to reduce climate change impacts on sea turtle reproduction, provided by experts surveyed in the study by Fuentes and Cinner (2010).

 

Sea turtles have key roles in the ecological function of marine ecosystems, as they help maintain seagrass beds and are a valuable part of the tourism industry for many nations. It is vital to understand how the changing environment will influence risks for current and future sea turtle populations around the world. Minimizing further anthropogenic impacts, conserving existing populations and habitats, and further investigation of sea turtles’ ability to adapt to increasing temperatures is critical to protecting these marine organisms.

 

References:

Howard, Robert, Ian Bell, and David Pike. “Tropical Flatback Turtle (Natator Depressus) Embryos Are Resilient to the Heat of Climate Change.” Journal of Experimental Biology 218 (2015): 3330-335. Web. 1 Feb. 2016.

Fuentes, M.M.P.B., and J.E. Cinner. “Using Expert Opinion to Prioritize Impacts of Climate Change on Sea Turtle’s Nesting Grounds.” Journal of Environmental Management 91 (2010): 2511-518. Web. 1 Feb. 2016.

Laloë, Jacques-Olivier, Nicole Esteban, Jessica Berkel, and Graeme Hays. “Sand Temperatures for Nesting Sea Turtles in the Caribbean: Implications for Hatchling Sex Ratios in the Face of Climate Change.” Journal of Experimental Marine Biology and Ecology 474 (2016): 92-99. Web. 1 Feb. 2016.

M.M.P.B. Fuentes, M. Hamann, and C.J. Limpus. “Past, Current and Future Thermal Profiles of Green Turtle Nesting Grounds: Implications from Climate Chang.” Journal of Experimental Marine Biology and Ecology 383 (2010): 56-54. Web. 1 Feb. 2016.

Santos, Katherine Comer, Marielle Livesey, Marianne Fish, and Armando Camago Lorences. “Climate Change Implications for the Nest Site Selection Process and Subsequent Hatching Success of a Green Turtle Population.” Original Article Mitigation and Adaptation Strategies for Global Change (2015): n. pag. Web. 1 Feb. 2016.

Standora, Edward A., and James R. Spotila. “Temperature Dependent Sex Determination in Sea Turtles.” Copeia 1985 (1985): 711-22. Web. 1 Feb. 2016.

Tapilatu, Ricardo F., and Ferdiel Ballamu. “Nest Temperatures of the Piai and Sayang Islands Green Turtle (Chelonia Mydas) Rookeries, Raja Ampat Papua, Indonesia: Implications for Hatchling Sex Ratios.” Biodiversitas 1st ser. 16 (2015): 102-07. Web. 1 Feb. 2016.

Clean, Clear, and Under Environmental Control: The Coal Mining Industry’s Impact on the Great Barrier Reef

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By Casey Dresbach, SRC Intern

Australia’s Great Barrier Reef is home to 348,000 km (approximately 216237.175 miles) of marine ecosystems, an expansive realm is almost equivalent to the size of Germany. However, its grand location is at mercy to shipping channels, rail transport networks, major ports, and most detrimental, several coal mines. In July 2015, the World Heritage Committee called attention to the consequences of these coal deposits. Climate change, poor water quality, and coastal development are jeopardized for industrial preference. This multi-billion dollar coal industry is great economically but scientifically, the cons outweigh the pros. They are not particularly fixing anything. They seem to touch upon the short-term effects and not the long term. Research has shown that the integration of both short and long term impacts could potentially serve a far more effective plan for change.

Aerial Shot of Reef JPEG aligned center (Caption: Photograph of The Great Barrier Reef shot from a helicopter ride over the Reef at the Witsunday Islands, Australia.).

Photograph of The Great Barrier Reef shot from a helicopter ride over the Reef at the Whitsunday Islands, Australia.).

Coal power plant emissions contain several toxic elements that suffocate the environment. Global warming comes hand in hand with the emissions as far too much C02 is released into the air. Not only do those emissions affect the air but also the ocean’s pH level.  Ocean acidification becomes the reality, which ultimately leads to bleaching of the corals. Environmental impact statements (EISs) are currently instated to assist Australian Governments and Queensland to consider the impact of new coal mining proposals when deciding whether to approve them and inform the development of appropriate conditions for environmental management. Their role is to describe the environment’s current state which is extremely beneficial but the problem here is that they only report direct local impacts of mining operations and do not consider the indirect impacts of the mines at a broader spatial or temporal scale. Australia’s Reef is massive and the EISs do not consider its vastness. It is so crucial to understand the incremental accumulation of impacts, which have led to its own decline.

Consequences of Coal Industry JPEG aligned in text to the left (Caption: Schematic condition of a mine fire configuration, with emissions of dust, fine particles, radon, mercury vapor, CO, CO2, NOx, SO2, etc… source pollution and gas contributing to the greenhouse effect.).

Schematic condition of a mine fire configuration, with emissions of dust, fine particles, radon, mercury vapor, CO, CO2, NOx, SO2, etc… source pollution and gas contributing to the greenhouse effect.).

A World Heritage Site is a place that is listed by the United Nations Educational, Scientific and Cultural Organization (UNESCO) as being of special physical significance. The Great Barrier Reef is categorized as such and the failure of the EISs to consider the progressive factors coal mining inundates has led to sharp decreases in World Heritage values.

An alternative assessment to the EISs is the Cumulative Impact Assessment (CIA) which systematically analyzes, evaluates, and predicts cumulative environmental change over time and across a grand spatial extent of a particular environment, focusing on pressures of interactions. For example, they would hone into the negatives of coal mining in combination with already polluted land from said mining. They might also combine such interaction with the present coastal development and its potential impact on climate change. CIAs are all encompassing and they focus on the broader, the potential, what could happen in time to come.

We should make the CIA the primary choice of assessment even though there are barriers to cumulative impact assessments. The Reef 2050 Plan is the framework set for protecting and managing the Great Barrier Reef from 2015 to 2050. The issue is that it hasn’t managed to establish accuracy in long-term research models. They focus on qualitative studies rather than the broader interactive research to better understand potential problems in the future. The continuing of such failure will send us back to EISs, which are far from influential leading to more piecemeal decisions that ignore the lengthy and extensive accumulation of impacts responsible for the Reef’s decline.

Moving forward, independent CIA commissions should be instated to se the terms of reference, review the assessment’s outputs by deeming them continuous or not, and initiating public input by ensuring well established time frames and focusing on the long term issues. The Great Barrier Reef should most definitely have precedence over the coal industry because coal isn’t the hottest commodity today. Given its predicted to slow anyway, Australia Bank is no longer planning to fund mining projects. Neither are Deutsche Bank, HSBC, Morgan Stanley, Citigroup and other lenders because they’re nervous of jeopardizing their reputations. The consequences the coal industry allocates to the environment are no secret yet the trade still seems to continue its operation year after year. All potential funders are aware of the negatives and don’t want their names paired with such negativity. We need to standardize and focus on the long term issues of coal mining and less so on the business or monetary gains from the industry.

 

References

Ackerman, S. (2009, December 27). Amazing Great Barrier Reef 1. Retrieved January 11, 2015, from Wikimedia Commons: https://commons.wikimedia.org/wiki/File:Amazing_Great_Barrier_Reef_1.jpg

Bretwood Higman, G. T. (n.d.). Coal Seam Fire. Retrieved from Ground Truth Trekking: http://www.groundtruthtrekking.org/Graphics/CoalSeamFires.html

Grech, A., R. L. Pressey, and J. C. Day. “Coal, Cumulative Impacts, and the Great Barrier Reef.” Conservation Letters (2015).

 

Why have global shark and ray landings declined: improved management or overfishing?

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Paper by Lindsay N K Davidson, Meg A Krawchuk, Nicholas K Dulvy

 

By Pat Goebel, SRC Intern

A drop in shark and ray landings may be thought of as a success for in improved management strategies. However, in the case of Davidson et al (2015), that is too good to be true. Unfortunately, the decline in global shark and ray landings has been attributed to overfishing and other ecosystem influencers.

Sharks and rays are commercially valuable for their fins, meat, liver, oil and skin with their fins and meat. The demand for shark products is relatively new concept, as their commercial value has increased with the decline of other valuable fisheries. As on could assume with supply and demand, the high demand of shark products leads to an increase in fishing pressure. The increase in fishing pressure combined with the lack of laws regulating the shark and ray fishery, lead to the depletion of shark and ray populations. The rapid decline in shark and ray populations resulted in new management strategies. Davidson et al (2015), investigated these new management strategies to determine if declines in shark and ray catches were a result of the fisheries management performance or overfishing.

Figure 1 - Shark_fins_Taiwan

Shark and ray landings peaked in 2003 and have declined by about 20% in the past decade. Davidson et al. (2015), noted that the decrease is more likely related to overfishing than management implementations. The official harvest number used in this study is possibly two to three times below the actual number of sharks and rays being caught. This study highlights the fact that sharks and rays are being harvested at an unsustainable rate. Moreover, Davidson et al (2015), stressed several countries that warrant prioritization for conservation and management action. The greatest declines were reported in Pakistan and Sri Lanka, both of which have little to no management or enforcement. If new management strategies are not implemented into these countries, elasmobranch populations will continue to be harvest at a detrimental scale.

Figure 2. Global distribution of (a) country-specific shark and ray landings averaged between 2003 and 2011 and mapped as a percent of the total. (b) the difference between the averages of landings reported in 2001-2003 and 2009-2011

Figure 2. Global distribution of (a) country-specific shark and ray landings averaged between 2003 and 2011 and mapped as a percent of the total. (b) the difference between the averages of landings reported in 2001-2003 and 2009-2011

 

A case for the importance and management of fish spawning aggregations

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By Rachel Skubel, SRC Intern

Every year, at least 300 species of fish will go to a specific spot in the ocean, at a specific time, for a key event in the continuation of their species: spawning, or releasing eggs to be fertilized. Erisman et al. (2015) detail why these fish spawning aggregations (FSAs) are hotspots of productivity, and why they are intuitive areas to protect.

Over time, fish species come to regularly spawn at these locations in order to maximize fitness (i.e. the survival of their offspring, and thus the propagation of their genes). FSA sites are defined by geomorphology and oceanography that yield high productivity (i.e. upwelling around seamounts that bring nutrients and high primary production), allowing the eventual larvae to feed and increase chances in the larger ocean arena. Not only do spawning fish and their offspring benefit, but the influx of eggs (‘egg boon’) creates a nutrient-dense food source for other animals – this is an example of a ‘trophic cascade’ that can support the health of an ecosystem. Further, marine animals on a migratory route (such as whale sharks) can feed from the resulting feast – which means FSAs are important links between ecosystems. Typically timed with seasons and lunar cycles, many species (up to tens of species) will come to spawn at one FSA site.

Clearly, protecting FSAs is an effective conservation strategy – the benefits go far beyond the spawning species in question, and authorities receive a very high ‘bang for their buck’ so to speak. Protecting one area can replenish numerous species across their ranges. And yet, focused management strategies are lacking.

How do humans fit in the picture?

What with their being so predictably productive over a small area, there are many fisheries associated with FSAs – from commercial to recreational and subsistence. This illustrates the importance of proper management, as overexploiting a species in such a small space, during an important life history event, can impact the fish over a huge spatial and temporal range. The Nassau grouper (Epinephelus striatus) is an excellent example. Formerly a productive and important fishery species in the Caribbean, prolonged overfishing resulted in FSAs being extinguished across its territory. Now, it is listed as endangered by the International Union for the Conservation of Nature.

How are FSAs protected?

Less than 35% of known FSAs receive any amount of protection from marine protected areas. An estimated 52% of FSAs remain unassessed, and of the 906 documented sites (see Russell et al. 2014; Figure 1), most are at reefs and in tropical waters – meaning cold-water aggregations are ripe for discovery and protection. The congregation of so many individuals at a predictable time at one location means that FSAs are valuable for recurring stock assessment. The IUCN World Conservation Congress (circa 2014) recommended governments create management measures that would sustainably protect reef fish and their spawning aggregations, as well as directing NGOs and fishing management organizations to take up the issue. Due to their recurring nature, protection of FSAs is effective for many of the same reasons fishing them is – managers know just which times and places would be most effective for a fishery closure, and this closure is predictable for the resource users as well.

 

The global distribution of known fish spawning aggregations (Erisman et al. 2015, based on data from Science and Conservation of Fish Spawning Aggregations Global Fish Spawning Database scfra.org/database)

The global distribution of known fish spawning aggregations (Erisman et al. 2015, based on data from Science and Conservation of Fish Spawning Aggregations Global Fish Spawning Database scfra.org/database)

In Europe, the European Union’s Common Fishery Policy now directs the retention of a stocks’ full reproductive capacity to achieve ‘Good Environmental Status’, yet the UK’s Marine Management Organization may implement a spatial zoning approach that prioritizes fishing activity over other uses of a given area. In the US, the Magnusson-Stevens Act (MSA) recognizes FSAs as essential fish habitat (EFH), which fishery management bodies are mandated to minimize fishing impacts upon.

Continuing with the Nassau Grouper example, the Bahamian Government has implemented an annual closed season for the species from December 1st to February 28th to protect their spawning aggregations, which means that ‘taking, landing, possessing, selling, and offering for sale’ is prohibited, and can result in a fine of $5000 or a one-year imprisonment (http://www.thebahamasweekly.com/publish/bis-news-updates/Closure_of_Nassau_Grouper_Fishing_Throughout_The_Bahamas38666.shtml). Dr. Kristine Stump of the Shedd Aquarium is currently studying these ecologically and economically important fish during their breeding seasonin the Bahamas, combining acoustic telemetry, genetic analysis, and blood sampling (http://www.huffingtonpost.com/kristine-stump/nassau-grouper-a-beautiful-fish-at-risk_b_8227446.html).

Going forward, the best chance for successful protection of FSAs may lie in community participation to ensure compliance by fishers. The Coastal Conservation Association in the US is composed of recreational fishers, who were in support of seasonal closures for the Warsaw grouper and speckled hind, realizing that this would allow them to fish the species at other times of the year, for years to come. Effective design is also important; in the Caribbean, the Caribbean Fishery Management Council and South Atlantic Fisheries Management Council aim to establish networks of reserves to protect reef species. Erisman et al. have made an excellent case for the protection of FSAs, and their potential to serve as a success story across conservation and fisheries sectors.

 

Works cited

Erisman, B., Heyman, W., Kobara, S., Ezer, T., Pittman, S., Aburto‐Oropeza, O., & Nemeth, R. S. (2015). Fish spawning aggregations: where well‐placed management actions can yield big benefits for fisheries and conservation. Fish and Fisheries. doi: 10.1111/faf.12132

Russell, M.W., deSadovy Mitcheson, Y., Erisman, B.E., Hamilton, R.J., Luckhurst, B.E. & Nemeth, R.S. (2014) Status Report – World’s Fish Aggregations 2014. Science and Conservation of Fish Aggregations, California USA. International Coral Reef Initiative.