Olive Ridley Arribadas

November 21, 2013/0 Comments/in Conservation, Ocean News /by aanstett

by Daniela Escontrela, RJD Intern

Olive Ridley sea turtles, also known by their scientific name of Lepidochelys Olivacea, are as their name suggests an olive color. They have a heart shaped carapace (or top shell) and have either one or two claws on their flippers. These turtles tend to reach sexual maturity around 15 years of age, which is relatively young compared to other species of sea turtles; once they reach sexual maturity they nest about once or twice per season laying on average about 100 eggs per clutch. (NOAA 2013) Olive Ridleys are the most abundant sea turtles in the world, with 800,000 females nesting annually; however, they are listed as vulnerable under the International Union for Conservation of Nature. (Valverde et al 2012) In fact, the population of Olive Ridleys has seen a decline of about 60% since the 1960s. (NOAA 2013).

These turtle seem like any other species of turtle; they’re born, swim out to sea, come back and lay their nest, go back to sea and repeat this cycle over the course of its life. However, this genus of turtles (which includes the Olive Ridley and Kemp’s Ridley) demonstrate a particularly interesting behavior not observed in any other turtles; in fact this behavior can be considered a spectacle of nature. These turtles participate in something known as an “arribada”. An arribada is a mass nesting behavior were tens of thousands to hundreds of thousands of sea turtles come onto the beach to nest over the course of a couple of days. For most people, a nesting event is considered an arribada when more than 100 turtles are on the beach at the same time. (Valverde et al 2012) Although Olive Ridleys nest in over 40 countries, arribadas are only observed in a few countries: Mexico, Nicaragua, Costa Rica, Panama and India. No one really knows why these events happen or how the turtles know when it’s time to come ashore in mass. Some theories as to what triggers these events include offshore winds, lunar cycles and release of pheromones by females, but much research remains to be done. (NOAA2013)

Olive Ridley turtle nesting at Nancite beach in Costa Rica (Photo taken by Edith Shum)

Over the summer, I had the pleasure of traveling to Costa Rica, and as luck would have it, I had the opportunity to spend two weeks in Nancite beach, one of the beaches in Costa Rica were arribadas occur. The beach is located in Santa Rosa National Park and permits are required to go there. It is in an extremely remote location; in fact, to get there from the capital (San Jose) we had to take a four hour bus ride, then a two hour jeep ride and on top of all that a very laborious two hour hike. Nancite beach is small, only about one kilometer long, but regardless, during an arribada thousands of females come ashore to nest. Arribadas seem like a godsend for yet another species that is suffering from declines in population numbers; but arribadas aren’t as beneficial as they seem. When too many female turtles come to nest at once, nests that were already laid tend to be dug up by other females as they make their own nests. In addition, hatchling survival rate is very low and this may play a crucial role in the observed decline of nesting females at Nancite beach and the reduced frequency of arribadas. In fact, research revealed many nests showed no evidence of embryonic development. This may be due to high embryonic mortality at early stages or because a lot of the eggs are infertile, which could be explained by the low observations of mating in front of Nancite. (Valverde et al 1998) Some other challenges and reasons for decline will be discussed a little later.

An image of Nancite beach, one of the main arribada spots in Costa Rica (Photo taken by Edith Shum)

Another arribada beach in Costa Rica is Ostional Beach which is also located on the northwest coast of Costa Rica. It was deemed a wildlife refuge 1983; in comparison to Nancite, this beach is a lot bigger, about seven kilometers. This important rookery was discovered in 1970 and it’s the second largest arribada beach in the world, second only to the one in La Escobilla, Mexico. What makes this beach different, is that it is the only beach in Costa Rica were harvesting of eggs is allowed. The small town of Ostional only has about 450 residents and since the legalization of egg harvesting in 1987, the people of Ostional have been doing just that. This legalization wasn’t without foundation; just like in Nancite Beach, a lot of egg clutches were being destroyed by other females during arribadas and hatchling success rates were very low, so maybe if some of the eggs were harvested, there would be a better chance of survival for the other clutches. In addition, legalization could help with the previously illegal take of eggs. So the community founded the Association for Integral Development at Ostional (the acronym in Spanish is ADIO). With the program, associates would harvest during the first 2.5 days of an arribada event and in return they would keep the beach clean and reduce the impact of feral predators. The eggs are sold all over the country and the proceeds go to both the associates and the community members. The problem with the program is that there seems to be no research to indicate the viability of the program; in fact in the past two decades, the amount of females that lay eggs at Ostional has decreased. (Valverde et al 1998)

An arribada event at Ostional beach in November 2006. This event at around 62,000 Olive Ridleys

Before we can jump to conclusions and blame the harvesting of eggs for the declines seen in both Ostional and Nancite, other factors have to be taken into account. Like mentioned before, arribadas aren’t as good as they seem, for one, females tend to destroy other nests as they build their own. The low hatchling success rates are another reason for concern. The low rates of success may be due to the high amounts of microorganisms that are related to the large number of clutches laid during arribadas. As Valverde explains “microorganism proliferation is thought to be a result from the increased amount of egg derived organic matter found in these beaches as a direct consequence of nest destruction by other nesting females”. Because of the high amounts of decomposing organic material from the broken eggs, oxygen levels also decrease which would create an anoxic environment for the eggs and hence prevent growth and development. It is possible that the egg harvest could be of crucial help as it would be removing eggs that otherwise would be destroyed and therefore decompose in the sand, deteriorating the conditions for the other surviving eggs clutches. (Valverde et al 1998)

At Nancite beach, many eggs are washed out during high tides; egg clutches are also highly predated on. The removal of these eggs may help better the quality of the sand for the other eggs that are left (Photo taken by Dani Escontrela)

Olive Ridleys differ from other sea turtles in another way, they are highly nomadic. While most other turtles follow, to a certain extent, specific routes between their foraging grounds and nesting grounds, Olive Ridleys do not. Olive Ridleys have been tracked mostly in pelagic waters and have been found as far north as Mexico and as far south as Peru. There isn’t one exact place where this species goes for food, in fact it is believed that this turtles eat as they swim, they are opportunistic feeders. (Plotkin 2010) These migratory patterns can make them especially susceptible to overfishing in different countries where there may be no laws against the capture of sea turtles. In fact for a long time, the Olive Ridleys were fished at high rates by the Ecuadorian and Mexican fisheries; fortunately, fishing of sea turtles was banned in 1981 and 1990 respectively. Another danger faced by the Olive Ridley is the incidental mortality in shrimp nets, in which case turtles aren’t the target species of the fishery but are instead caught as by catch. In 1993 alone 60,000 turtles along the Pacific coast of Central American were killed by this method of fishing. Declines at both beaches can also be explained by beach exchange, were turtles change the beaches were they lay their nests. In fact, while I was in Nancite beach, we would often get Olive Ridleys that had been marked at Ostional beach. (Valverde et al 1998)

As grim as this all sounds, the future may not be so bleak for this species. As long as we put the time and effort we may be able to keep this species of turtle around. The fact that these turtles are nomadic doesn’t have to be a problem; fishing regulations need to be put in place in the countries the turtle frequents and also in international waters. However, there is actually a positive side to the turtles being nomadic too. Because the turtles show plasticity in their migration patterns, in times of environmental change, such as an El Nino event, the turtles would be able to move to different areas and find food. This means that Olive Ridleys might be more resilient when it comes to climate change. (Plotkin 2010) On another note, Valverde discovered in his research that Olive Ridley hatchlings showed the greatest success during the rainy season, in cooler temperatures and when clutch density is low. It is recommended then, that egg harvesting is restricted during these occasions to ensure the highest success for these hatchlings. (Valverde 2012)

The future also lies in continued research. We must keep evaluating and try to determine what is causing population declines at certain beaches and address these problems. In addition, more research needs to be done to figure out the viability of the egg harvesting program in Ostional; if it is deemed successful and viable, it should be continued and potentially be carried out in other arribada beaches with low hatchling success rates due to high density of clutches. All these efforts need to be taken not just by Costa Rica, but also by other countries where the Olive Ridley frequents seeing as the turtles are a shared resource and therefore should be protected by everyone.

REFERENCES

“Olive Ridley Turtle (Lepidochelys olivacea).” NOAA Fisheries Office of Protected Resources. N.p., 1 Mar. 2013. Web. 2 Oct. 2013. <http://www.nmfs.noaa.gov/pr/species/turtles/oliveridley.htm>.

Plotkin, Pamela T. “Nomadic behaviour of the highly migratory olive ridley sea turtle Lepidochelys olivacea in the eastern tropical Pacific Ocean.” Endangered Species Research 13.1 (2012): 33-40. Print.

Valverde, R. A., et al. “Olive Ridley Mass Nesting Ecology and Egg Harvest at Ostional Beach, Costa Rica.” Chelonian Conservation and Biology 11.1 (2012): 1-11. Print.

Valverde, Roldan A., Stephen E. Cornelius, and Claudette L. Mo. “Decline of the Olive Ridley Sea Turtle (Lepidochelys olivacea) Nesting Assemblage at Nancite Beach, Santa Rosa National Park, Costa Rica.” Chelonian Conservation and Biology 3.1 (1998): 58-63. Print.

Towards Improved Socio-Economic Assessments of Ocean Acidification’s Impacts

November 18, 2013/0 Comments/in Conservation, Ocean News /by aanstett

by Heather Alberro, RJD Intern

This article focuses on the issue of ocean acidification and the complexity of its impacts on the marine environment, marine organisms, and on humans societies that depend on the goods and services provided by thriving oceans. The authors of the article stress that, due to the trans-disciplinary nature of the causes and effects of ocean acidification, a more holistic approach should be adopted in order to study this problem more effectively. Any policies addressing ocean acidification, as well as other environmental threats, should be implemented with concern for current as well as future impacts of such policies. This article points out the salience of the 2010 International Workshop in Monaco, a remarkable step towards more holistic research, which brought economists and scientists together in order to combine their contrasting knowledge bases and thus facilitate a multidisciplinary approach to ocean acidification studies.

Global ocean acidification projections

Ocean acidification has been spurred largely by CO2-increasing anthropogenic activities such as the burning of fossil fuels. The oceans sequester CO2, but as the amounts being taken up increase, ocean acidification occurs, after a series of chemical processes. CO2 sequestration by the oceans does help mitigate the effects of climate change, yet these increases in CO2 sequestration also alter the ocean’s chemistry. Current data on the effects of ocean acidification on ecosystems and organisms is limited and only just beginning to be understood. Some direct effects include physiological disruptions such as changes in behavior and reductions in fertility. However, the indirect effects of ocean acidification are much more difficult to predict and analyze because of the complex nature of ecological interactions. Generalizations are difficult to make because the effects of ocean acidification vary across species, and very few species have been studied. More research is needed on the abilities of organisms to adapt to rising CO2 levels, as well as on the dynamics between ocean temperature, CO2, and other environmental factors, particularly in coastal regions where these dynamics are not so well understood. Further research would help gage the socio-economic effects of ocean acidification on coastal communities dependent on tourism and other goods from the oceans. Research would also greatly facilitate the implementation of effective socio-economic policy.

A SAMI pCO2 censor at NOAA CREWS station. Censor colelcts pCO2 and temperature data for the analysis of the effects of ocean acidification on coral reef ecosystems.

The article noted the need for a more thorough understanding of the ability of societies to adapt to future changes brought on by ocean acidification. The interactions between societies and the environment are indeed complex and multifaceted, as the attempts to address such interactions should be. Therefore, models designed to study these interactions should be designed to explore their multidimensional nature, not just one side of the relationship, as both ends indeed influence each other. Research programs must be designed which bring together biologists and economists in order to gain more insight into the “bio-socioeconomic” effects of ocean acidification. Effective research and policy take into consideration the various factors that shape particular issues of concern. Therefore, in the case of ocean acidification, one can’t simply study it in isolation from other environmental occurrences such as climate change and biodiversity loss. Often, such issues are very much intertwined. The same idea applies to approaches to research. One must adopt multidisciplinary strategies that incorporate input from various fields of study, ranging from economics and sociology to biology and chemistry. The further these various approaches are integrated in research, the more accurate the data and extrapolations will be, along with their relevance to society.

Florida Marine Life Dying From Pollution

November 14, 2013/0 Comments/in Conservation, Ocean News /by aanstett

by Chelsea Olson, RJD Intern

While much of the attention as of lately has been on Japan and the Fukushima radiation’s potential effects, a source of serious concern has been spreading in our own backyards. Many of Florida’s waterways are becoming increasingly polluted and, in turn, affecting local marine life, the ocean and our ecosystem. This also directly affects humans who rely on safe ocean water to fish from and swim in.

Due to the heavy rainfall this past summer, Lake Okeechobee has needed to release excess water into surrounding canals and estuaries to prevent a breach of the lake’s levees. Lake Okeechobee’s water lowers the salinity, carries dirt that makes the water murky, and carries high levels of two pollutants that bring major problems: nitrogen and phosphorus (Allen). Taylor Creek in Fort Pierce, St. Lucie River and Indian River Lagoon are all receiving this polluted overflow (McCorquodale).

Indian River Lagoon. Source: Wikimedia Commons

In Indian River Lagoon alone, which has now been deemed a “killing zone” and “mass murder mystery,” there have been 46 dolphins, 111 manatees, 300 pelicans and 47,000 acres of sea grass beds killed off (McCorquodale). Much of this comes from large, toxic algae blooms that have formed due to the abnormal water conditions and pollutants. These blooms have destroyed sea grass beds, which comprise a majority of a manatee’s diet. Now they’re eating a red seaweed macro algae that’s become toxic with the lagoon’s unnatural growing conditions (Allen).

First documented case of Lobomycosis on a dolphin, 1993. (BDFS Brazil)

But this isn’t exactly a recent phenomenon. A yeast-like infection called lobomycosis, previously known to be an exclusively human disease, was first documented on a bottlenose dolphin in southern Brazil in 1993. This female adult was found in a river estuary, which has a mix of fresh and salt water conditions (BDFS Brazil). In 2006, a study was conducted to determine if there was a strong presence of lobomycosis in dolphins at the Indian River Lagoon. It was concluded that “lobomycosis may be occurring in epidemic proportions among dolphins in the Indian River Lagoon (Reif).” Lobomycosis was found in dolphins captured in the southern part of the lagoon, where freshwater intrusion was found, along with lower salinity levels, suggesting that “exposure to environmental stressors may be contributing to the high prevalence of the disease (Reif).”

While marine life deaths rise and toxic algae continues to grow, local Florida politicians have declared a crisis and are seeking the help of the government for solutions. It appears to be a two-fold process, however, both of which won’t help with the short-term crisis. Scientists point to the need of ceasing drainage from Lake Okeechobee into the Indian River Lagoon altogether and redirecting its natural flow to the south through the Everglades. There’s also the larger and more difficult issue of septic systems still being in place among these counties on the lagoon. “Over 1 million kilograms of nitrogen a year are going toward the Indian River Lagoon from septic tanks alone,” says Brian Lapointe, a research professor at Harbor Branch who’s been working on the lagoon’s crises for 40 years (Allen).

One can only hope that politicians, marine researchers and communities can all work together toward a long-term solution. This region badly needs to restore its ecosystem so that residents can once again partake in fishing, swimming and the everyday practices of a coastal town.

REFERENCES

Allen, Greg. “With Murky Water And Manatee Deaths, Lagoon Languishes.” NPR. NPR, 26 Sept. 2013. Web. 16 Oct. 2013.

BDFS Brazil. “First Case of Lobomycosis in a Bottlenose Dolphin from Southern Brazil.” Marine Mammal Science 9.3 (1993): 329-31. Google Scholar. Web. 22 Oct. 2013.

Indian River Lagoon, Florida. 2006. Photograph. US Fish and Wildlife Service, Florida. Wikimedia Commons. Wikipedia, 6 Apr. 2006. Web. 22 Oct. 2013.

McCorquodale, Amanda. “Devastating Photos Of Florida Pollution Will Fill You With Rage.” The Huffington Post. TheHuffingtonPost.com, 02 Oct. 2013. Web. 16 Oct. 2013.

Reif, John S., DVM. “Lobomycosis in Atlantic Bottlenose Dolphins from the Indian River Lagoon, Florida.” Journal of the American Veterinary Medical Association 228.1 (2006): 104-08. AVMA. American Veterinary Medical Association, 15 July 2008. Web. 16 Oct. 2013.

Carbon Dioxide Exposure Influences Habitat Choice of Coral-Associated Fish

November 13, 2013/0 Comments/in Conservation, Ocean News /by aanstett

by Hannah Calich, RJD Intern

Elevated carbon dioxide (CO₂) levels have been shown to not only impact the health of coral reefs, but the health of coral reef associated fish as well. Coral-dwelling gobies are among the most habitat-specialized fish on coral reefs. Since these fish are rarely found outside of their preferred habitat they are a great species to monitor when trying to determine how CO₂ levels influence the habitat choice of reef-fish.

A recent study by Devine and Munday (2013) aimed to determine how short-term exposure to high CO₂ levels influences the habitat preference of coral-dwelling gobies. This study used two goby species, yellow-green gobies, Paragobiodon xanthosomus, who preferentially inhabit only one coral species and broad-barred gobies, Gobiodon histrio, who preferentially inhabit a small number of coral species. The gobies were caught in the wild (Lizard Island, Australia) and moved to aquaria with continuous seawater pumps. The pumps either diffused ambient seawater (as a control, 440 µatm CO₂), or high levels of CO₂ (880 µatm) into the water. The fish remained in the aquaria for 4 days before the experiments began.

Laboratory Olfactory Cue Experiment

A laboratory experiment was used to determine if yellow-green gobies that have been exposed to high levels of CO₂ can distinguish between two olfactory (scent) cues. To do this, a goby that had been exposed to either ambient seawater or high levels of CO₂was put into a container with two different coral species. The goby could not see the corals, but was able to smell them. The coral species were Seriatopora hystrix (the preferred coral species of yellow-green gobies) and Pocillopora damicornis (a non-preferred coral). The researchers noted which coral species the goby associated with during a 2-minute observation period. If the goby did not approach either coral it was recorded as making “no choice”. This procedure was repeated for 20 control gobies and 19 CO₂ exposed gobies.

Field Habitat Choice Experiment

A field experiment was used to determine if broad-barred gobies could locate an alternative habitat if their host coral died. To begin, a goby that had been exposed to either ambient seawater or high levels of CO₂was released over a dead colony of Acropora nasuta (the preferred coral species of broad-barred gobies). Surrounding the dead coral was live colonies of A. nasuta and Acropora tenuis (a non-preferred coral species). Each goby had the option of either staying on the dead coral, moving to a live preferred coral, or moving to a live non-preferred coral. After 24 hours the researchers came back to the reef and documented what habitat the goby chose. This procedure was repeated for 20 control gobies and 20 CO₂ exposed gobies.

Laboratory Olfactory Cue Experiment

When yellow-green gobies were exposed to ambient seawater (as a control) they chose to swim towards their host corals 70% of the time. In contrast, the gobies exposed to elevated CO₂ displayed no preference for their host coral. In fact, only 16% of the gobies swam towards the host coral, 42% swam towards the non-host coral, and 42% did not choose a coral.

The number of control and CO2 exposed yellow-green gobies that associated with each coral, or displayed no preference. The black bars represent gobies exposed to ambient seawater and the white bars represent gobies exposed to elevated CO2. From left to right the gobies chose to move towards the preferred coral species (S. hystrix), the non-preferred coral species (P. damicornis), or neither. From Devine and Mumby 2013

Field Habitat Choice Experiment

Within 24 hours of being released over a dead host coral, 100% of the broad-barred gobies that were exposed to ambient seawater had relocated to a live preferred coral. In comparison, only 45% of gobies exposed to elevated CO₂ moved to a live preferred coral, 10% moved to a live non-preferred coral, and 45% remained on the dead coral.

The number of control and elevated CO2 exposed broad-barred gobies associated with each habitat type 24 hours after they were released over dead A. nasuta. The black bars represent gobies exposed to ambient seawater and white bars represent gobies exposed to elevated CO2. From left to right the coral choices were a live preferred host (A. nasuta), a live non-preferred host (A. tenuis), and a dead preferred host (where the gobies were initially released, A. nasuta). From Devine and Mumby 2013

Healthy gobies (those raised in ambient seawater) were more attracted to the scent of their preferred coral species than the scent a non-preferred coral species. Additionally, healthy gobies would move from a dead coral to a live preferred coral. However, gobies that had been exposed to high levels of CO₂ were rarely attracted to their preferred coral species. Additionally, when the CO₂ exposed gobies were released on a dead coral they may not leave it.

Results from this study suggest that permanently elevated CO₂ levels may significantly impact the ability of highly specialized fish to locate suitable habitat types following disturbances such as coral bleaching. If a goby is unable to locate a suitable habitat type it will be vulnerable to predation, malnutrition and eventually, death.

Occasionally, a goby may decide to inhabit a non-preferred coral when its preferred coral host dies. This is not an advantageous strategy for the goby as it is adapted to living within its preferred coral. Additionally, since gobies are naturally competitive, if they move onto a new coral they may displace other reef fish that were previously living on that coral. This displacement could theoretically cause a cascading effect that could influence the entire reef.

In conclusion, as CO₂ levels are expected to rise beyond the threshold of many coral communities within the next century, it is not only the corals that are at risk but the coral-associated species as well.

REFERENCE

Devine, B. M., & Munday, P. L. (2013). Habitat preferences of coral-associated fishes are altered by short-term exposure to elevated CO₂. Marine Biology, 160, 1955-1962. doi:10.1007/s00227-012-2051-1

The Reduction of Ocean Acidification Begins with Education

November 12, 2013/0 Comments/in Conservation, Ocean News /by aanstett

by Laurel Zaima, RJD Intern

The buildup of carbon dioxide in the ecosystem impacts more than just the earth’s climate. One of the most commonly known consequences of the surplus release of carbon dioxide into the atmosphere is global warming; however, changes in the ocean chemistry is also associated with the increased emission of CO₂. Ocean acidification (OA) is referred to as the “other CO₂ problem” that impacts the marine ecosystem by decreasing the pH of the ocean.

The increase in atmospheric and oceanic carbon dioxide concentrations result in an increasingly acidic pH in the ocean

The rising carbon dioxide levels are strongly accredited to the anthropogenic emission of carbon dioxide through the burning of fossil fuels, cement manufacturing, land use change, and other forms of human activity. If immediate action is not taken to reduce the buildup of CO₂, direct and indirect consequences from OA, such as extinction, will occur in the marine ecosystems. Exact predictions of the OA impact on the environment are uncertain due to the lack of knowledge and research about OA. Therefore, there is a necessity for more OA research and a greater educational outreach to the public in order to lower the carbon dioxide concentrations and reduce OA. G. Fauville, R. Säljö, and S. Dupont (2012) strive to address the issues of ocean acidification and the importance of public awareness and knowledge of environmental issues in their paper: Impact of Ocean Acidification on Marine Ecosystems: Educational challenges and Innovations. These scientists found that it takes more than just informing the public about the negative impacts of OA; a strong understanding of the OA threat is needed to change misconceptions and false ideas, and to create an adoption of environmentally friendly practices. A collaboration of educational methods to present environmental facts is a successful technique to provide adequate science literacy to students, teachers and the general public.

There are a variety of teaching methods that can be applied in two main forms of education: formal and informal education. Formal education refers to a guided curriculum that is taught by upper secondary schools and universities. Formal education of OA first requires teachers and professors to initially obtain accurate information from reliable peer-reviewed sources, and published factsheets by OA consortia or marine research centers. Once the teachers have created an OA curriculum for their students, they can begin implementing different educational methods that most effectively teaches the material. Students have a tendency to obtain more information when presented with the opportunity to conduct experiments to answer specific scientific inquiries. Therefore, the hands-on experiences, virtual hands-on experiences, and field experiments are all very successful formal methods in educating students about OA. Another formal education method is allowing students to be the knowledge creators and community educators. This process lets students contribute their knowledge about OA to the local and global community. The formal methods that offer an interaction between scientists and students, whether it is direct contact, virtual contact, or via scientific research papers, allows the students apply their knowledge about OA to real research and global scenarios. This personal interaction has the potential to instill a long-term interest in science for the students. The last formal education approach is learning through multimodal experiences by pairing recent advancements in digital technology with traditional experimentation. Students combined the OA data analysis that they collected from a hands-on experiment with the OA data analysis that they obtain from a virtual experiment, and they posted their results online to be shared all around the world.

Informal education typically utilizes media, such as newspapers, radio, television, the Internet, and science centers as the source of information. Science centers and science museums are very proficient in providing knowledge about climate change, and they often hold exhibitions, workshops, and hands-on activities for the public. Unfortunately, since OA is a relatively new topic, few science centers cover information about ocean chemistry changes. Movies and podcasts are two forms of popular media that address a variety of environmental issues, including OA.

Technology, Entertainment, Design (TED) is one of the popular educational podcasts that aims to spread ideas.

Each of the different formal and informal educational methods have benefits, but they also have time, money, and accessibility limitations. Overall, any of the virtual resources are the most economically reasonable for the consumer, and have the highest potential to be utilized long-term. However, the best way to reach scientific literacy among the public is to collaborate the different educational methods. Although ocean acidification is a new research area, the dire consequences of OA to the marine ecosystem are occurring fast. An increase in OA scientific research, and formal and informal education to the public can implement efficient CO₂ reduction strategies.

REFERENCES

TED Ideas Worth Sharing. n.p. 2013. Web. 7 Oct. 2013.

“Ocean Acidification increasing at unprecedented rate not seen in last 300 million years.” Climate Citizen. n.p. 12 Mar. 2012. Web. 7 Oct. 2013.

Artificial Reefs, Biodiversity, and Ecotourism

November 11, 2013/0 Comments/in Conservation, Ocean News /by aanstett

by Jessica Ann Wingar, RJD Intern

Coral reefs are a very important part of the ecosystem, and over the years, the condition of the world’s coral reefs has changed drastically; this condition has not changed for the better. There are many resources that coral reefs provide to the world. Some of these include tourism value and the fact that they provide a natural nursing area for fisheries. A lot of research has been done on corals and what features of a reef, give the reef more monetary value. This research has found some conflicting results. While, some claim that fish biodiversity is more valued than coral biodiversity, some claim the opposite. Although, this research has looked at many aspects of what makes a reef valuable, not a lot has been done with looking at the value of each component of the biological attributes of a reef. This study aimed to look at different levels of biodiversity in fish and corals, in addition to, looking at each condition under different levels of conservation effort. This study also looked at whether or not artificial reefs could be used to cause an increase in ecotourism across the world.

Researchers from the Ben Gurion University of Negev and the Interuniversity Institute for Marine Sciences at Eliat in Israel created a survey to give to divers in the city of Eliat in Israel to see what monetary values they would put on these artificial reefs. The survey presented a number of different biological conditions of artificial reefs and at varying levels of conservation effort. These biological conditions were coral size, coral diversity, fish abundance, coral abundance, varying numbers of fish and corals, and different levels of biodiversity of fish and coral. The survey also asked about how much money they would be willing to pay for each scenario and why they decided on that monetary amount.

The scenarios that the researchers used in the survey

This study showed that many of the divers would be willing to pay money for a more diverse environment that could be created by artificial reefs. The greatest motivation for paying more money was for their own enjoyment, but many of them also wanted to pay money to ensure that the reef would continue to exist. The survey showed that the divers wanted to pay more for fish species richness over abundance and they wanted to pay more for coral abundance rather than species richness.

An example of a scenario

Studies of this nature are very important because they show how recreational water activities can be used as a catalyst for conservation science. This ecotourism can be used as a tool for people to communicate conservation efforts. If people are willing to pay more for high biodiversity, then that is phenomenal because oceans thrive in higher biodiversity. Despite the fact that artificial reefs could help increase conservation awareness, they can sometimes attract certain types of organisms. Thus, creating a community built around them. Artificial reefs and transplantation of reefs hold a lot of potential to increase biodiversity and the health of today’s oceans.

REFERENCE

Polak, O, and Nadav Shashar. “Economic value of biological attributes of artificial coral reefs.” ICES Journal of Marine Science 70.4 (2013): 904-912.

Marine Protected Area Connectivity

November 8, 2013/0 Comments/in Conservation, Ocean News /by aanstett

by Hannah Armstrong, RJD Intern

More than 25% of the world’s fishery populations are considered overexploited or depleted, and 40% are heavily to fully exploited (Dayton PK, Sala E, Tegner MJ, Thrush S). In fact, some marine organisms have been driven extinct by human activity, while others remain close to extinction (Dayton PK, Sala E, Tegner MJ, Thrush S). In addition to other approaches, marine-protected-area design and implementation is an evolving tool to help conserve and manage these depleting fisheries. They are not only important for biodiversity conservation, but also as management and learning tools (Pujola JM, Schiavina M, Di Franco A, Melia P, Guidetti P, Gatto M, De Leo GA, Zane L.). Networks of marine protected areas, which differ in shape and size, help scientists evaluate theories of optimal shape and size for proper management and design, ultimately leading to adaptive management strategies (Pujola JM, Schiavina M, Di Franco A, Melia P, Guidetti P, Gatto M, De Leo GA, Zane L.). The effectiveness of marine protected areas, as well as the importance of marine protected area connectivity, however, does not seem to be fully understood.

In order to maintain ecosystem function, critical areas, such as fish spawning aggregation sites, need to be protected in marine protected areas.
(source: McLeod E, Salm R, Green A, Almany Jeanine. Designing marine protected area networks to address the impacts of climate change. Frontiers in Ecology and the Environment 7 (2009).)

Protected areas are becoming ever more critical in marine habitats, especially with increasing threats of overfishing, pollution and coastal development. When it comes to the design of marine protected areas and marine reserves, it is imperative that scientists and researchers consider patterns of connectivity. Marine connectivity is the bridge between marine habitats, occurring via larval dispersal as well as by the movements of adults and juvenile marine species; it is an important part of ensuring larval exchange and the replenishment of biodiversity in areas damaged by natural or human-related agents (McLeod E, Salm R, Green A, Almany Jeanine). Studies have shown that surface currents typically define dispersal patterns, but not all distribution is explained by passive drift alone; some migrations cause larvae to be transported in one direction by surface currents, and in another direction many hours later by subsurface currents (Dayton PK, Sala E, Tegner MJ, Thrush S). It is critical to study the connectivity caused by different marine organism behaviors and transport processes to ensure optimal conservation.

According to the IUCN, a marine protected network is a “collection of individual MPAs operating cooperatively and synergistically, at various spatial scales, and with a range of protection levels, in order to fulfill ecological aims more effectively and comprehensively than individual sites could alone” (McLeod E, Salm R, Green A, Almany Jeanine). The consideration of connectivity in marine protected area network design allows critical areas to be protected. Critical areas include nursery grounds, fish spawning aggregation sites, regions that feature high species diversity or high rates of endemism (habitat-specific), and areas that contain a variety of habitat types in close proximity to one another (McLeod E, Salm R, Green A, Almany Jeanine).

Overfishing has caused fisheries to be exploited or in some cases overexploited, making marine protected areas a much more critical tool in marine conservation.
(source: wikimedia commons http://commons.wikimedia.org/wiki/File:Theragra_chalcogramma_fishing.jpg)

In recent scenarios in which climate change has become a notable issue, it is also essential to protect areas that may be naturally more resistant or resilient to the threats associated with climate change (ie: coral bleaching) (McLeod E, Salm R, Green A, Almany Jeanine). Moreover, the potential for MPAs to change population sustainability, fishery yield, and ecosystem properties depends on the poorly understood consequences of three critical forms of connectivity over space: larval dispersal, juvenile and adult swimming, and movement of fishermen (Botsford LW, Brumbaugh DR, Grimes C, Kellner JB, Largier J, O’Farrell MR, Ralston S, Soulanille E, Wespestad V). Without taking into account these factors, connectivity amongst marine protected areas or networks is not possible.

Still, it is only once scientists and MPA implementers fully understand connectivity patterns that proper conservation techniques and MPA management can occur. Some data shows that a variety of marine species indicate that larval movements of 50-100km appear common for marine invertebrates, and from 100-200km for fishes (McLeod E, Salm R, Green A, Almany Jeanine). Some researchers believe that a system-wide approach should be adopted that addresses patterns of connectivity between ecosystems like mangroves, reefs, and sea grass beds to enhance resilience (McLeod E, Salm R, Green A, Almany Jeanine). If there is connectivity between linked habitats, then ecosystems can continue to function properly, or in some cases, recover from their depleted states. Those designing marine protected networks can use this data to determine the appropriate size of the reserve being implemented, allowing them to ensure larval connectivity.

Networks of marine reserves have become key tools in the effort to conserve our world’s oceans and the species therein. Future selection of marine protected areas and networks will depend on both the connectivity of targeted species, as well as the habitat quality of individual sites (Berglund M, Jacobi MN, Jonsson PR). Though there are opposing opinions regarding the most effective methods of marine biodiversity conservation, as well as with regard to the specific locations, sizes, and connectivity of marine reserves (Sala E, Aburto-Oropeza O, Paredes G, Parra I, Barrera JC, Dayton PK), there are growing research efforts to ensure successful conservation and management.

References

1.Christie MR, Tissot BN, Albins MA, Beets JP, Jia Y, et al. Larval Connectivity in an Effective Network of Marine Protected Areas. Plos One 5 (12) (2010).

2. Botsford LW, Brumbaugh DR, Grimes C, Kellner JB, Largier J, O’Farrell MR, Ralston S, Soulanille E, Wespestad V. Connectivity, sustainability, and yield: briding the gap between conventional fisheries management and marine protected areas. Reviews in Fish Biology and Fisheries 19 (1) (2009).

3. Planes S, Jones GP, Thorrold SR. Larval dispersal connects fish populations in a network of marine protected areas. PNAS 106 (14) (2009).

4. Sala E, Aburto-Oropeza O, Paredes G, Parra I, Barrera JC, Dayton PK. A General Model for Designing Networks of Marine Reserves. Science 298 (5600) (2002).

5. Berglund M, Jacobi MN, Jonsson PR. Optimal selection of marine protected areas based on connectivity and habitat quality. Ecological Modeling 240 (2012).

6. McLeod E, Salm R, Green A, Almany Jeanine. Designing marine protected area networks to address the impacts of climate change. Frontiers in Ecology and the Environment 7 (2009).

7. Pujola JM, Schiavina M, Di Franco A, Melia P, Guidetti P, Gatto M, De Leo GA, Zane L. Understanding the effectiveness of marine protected areas using genetic connectivity patterns and Lagrangian simulations. Diversity and Distributions, A Journal of Conservation Biology (2013).

8. Dayton PK, Sala E, Tegner MJ, Thrush S. Marine Reserves: Parks, Baselines and Fishery Enhancement. Bulletin of Marine Science 66 (3) (2000)

Extreme Breath Holding: Marine Mammal Diving

November 7, 2013/1 Comment/in Conservation, Ocean News /by aanstett

by Emily Nelson, RJD Intern

Sperm whales have been recorded diving to depths well over 2,000 meters. Elephant seals have recorded dives lasting over 2 hours. Humans, on average, can hold their breath underwater for less than 30 seconds. How is it that marine mammals spend such long periods of time underwater, diving to incredible depths? After all, they breathe oxygen just as terrestrial mammals do. The answer lies in the many adaptations these animals have acquired over time that completely change how oxygen is stored, delivered, and used in the body.

The incredible diving capabilities of marine mammals are shown in this table.

Contrary to what you may think, the lungs are not a primary site of oxygen storage in marine mammals. The purpose of the lung is to exchange gases between blood and the air. This function is largely restricted while diving; with increasing pressure, resulting from increasing depth, the lungs and trachea decrease in size and eventually collapse. However, this collapse helps to prevent nitrogen narcosis. Commonly known s the bends, this is a problem and concern for SCUBA divers. At depth nitrogen moves into the bloodstream rapidly and can cause gas bubbles to form in the body, blocking the flow of oxygen. In marine mammals, as lung size decreases air is forced into the upper airway spaces. These areas do not exchange gases with the blood and thus nitrogen is prevented from entering the blood stream altogether, allowing them to avoid the bends.

Despite decreased lung capacity, increased total body oxygen is a necessary component in the ability of marine mammals to hold their breath. /’|/Oxygen consumed during a dive is stored in three areas: muscles, blood, and lungs. Marine mammals have large stores of oxygen in their muscles and blood, acting almost like an on board scuba tank. Myoglobin (oxygen binding protein in muscle) is present at levels three to seven times higher than in terrestrial mammals. This internal store of oxygen is used for much of the animal’s aerobic metabolic needs. In addition, the amount of blood in a marine mammal is proportional to the depth at which it dives. Increased blood volume and hemoglobin (oxygen binding protein in blood) lead to higher oxygen stores. The concentration of red blood cells is also increased. Red blood cells carry oxygen, and as an animal starts a dive it sends red blood cells through the blood stream until it returns to the surface. The extent to which an animal shows these adaptations varies between species, but the amount of oxygen available and its utilization has a big impact on how long an animal can hold its breath for all marine mammals.

In addition to marine mammals’ increased ability to store oxygen, they can also decrease their oxygen consumption during a dive using bradycardia and selective ischemia. Bradycardia is a rapid decrease in heart rate upon starting a dive. An orca whale has the ability to go from a heart rate of 60 beats per minute to 30 beats per minute in a matter of 15 seconds. Heart rate during a dive is nearly the same as heart rate experienced during a respiratory pause. This decreased heart rate is then maintained for the duration of an animal’s dive. Because the heart is beating slower it is performing less work and oxygen consumption is reduced. The extent to which bradycardia occurs is proportional to the length of the dive, the longer a dive the slower the heart rate. As a dive nears completion an animals’ heart rate increases drastically in process known as anticipatory tachycardia.

Selective ischemia is the redistribution of blood to the most vital organs, the brain and heart. This deprives the kidneys and liver of blood and they may shut down during the dive. By limiting blood circulation oxygen is conserved and metabolic rate is decreased. Blood flow to muscles is minimal, but they still need to function in order to swim. Muscles can rely on internal myoglobin stores as well as anaerobic (without oxygen) metabolism. Muscles can withstand anaerobic metabolism due to their high tolerance for lactate. Upon surfacing blood flow returns to normal and these areas are flushed with blood, coming back to normal function almost immediately.

A humpback whale descending.

These are among the major adaptations marine mammals have gathered over time, allowing them to dive longer and to greater depths than any terrestrial mammal. They have the ability to readily adapt from surface conditions to conditions at extreme depths. However, there is still a lot to be learned about how these animals can survive under such unique circumstances.

REFERENCES

Hoelzel, A. Rus. Marine Mammal Biology: An Evolutionary Approach. Oxford: Blackwell Science, 2002. Print.

Kooyman, Gerald L. “Marine Mammal Diving.” Encyclopedia of Marine Mammals. 2^nd ed. Oxford: Academic, n.d. 327-32. Print.

Richardson, Jill. “Anatomy and Physiology II.” MSC 350. University of Miami, Coral Gables. Mar. 2013. Lecture.

Communicating Science Through Film

October 31, 2013/1 Comment/in Conservation, Ocean News /by aanstett

by Fiona Graham, RJD Graduate Student and Intern

Utilizing film as a media to communicate science can be a powerful way to quickly reach large numbers of the general public in a user friendly way. Whether it’s newly published scientific research, or you’re trying to promote scientific awareness for conservation purposes, choosing to create a short online based film about the topic is a great way to get involved in outreach and education. Promoting science through outreach is extremely important to conservation efforts, as, often, awareness about an issue can be a major barrier in conservation efforts. I see this first hand when conversations with new acquaintances inevitably turn to the “what do you do” small talk, and as a result of my research on sharks for my masters, I frequently find myself talking about shark population declines. It’s not surprising to me anymore that most people have no idea how threatened some shark species are, have never heard of shark fin soup, and don’t know what bycatch is.

Reaching the general public about these issues and new research results can be difficult, especially because non-scientists don’t often read published papers or necessarily speak the language. However, with the online resources we have available now it can be quite easy to quickly reach large numbers of people around the world. Social media platforms like Facebook, Twitter, and Instagram make sharing content simple. Short, online based films are a particularly great way to get across a message because it can be very engaging to the average person. In addition, a good educational film can easily be used again and again as a tool in classrooms around the world. Viewing platforms like YouTube and Vimeo can also give useful insight into view counts and the film’s audience demographic, helping to quantify outreach efforts.

Data from YouTube helps to quantify outreach efforts.

One of the reasons I love being a part of the RJ Dunlap Marine Conservation Program is that the value of outreach and communicating research is recognized and embraced. RJD has a full time media specialist and media focused interns that work with our scientists to communicate their research to the world through online virtual learning experiences, photographs and, of course, film.

Welcome to RJD, an introduction video. Watch it here: https://vimeo.com/21759088

In addition to the benefit that a film’s audience can derive from the experience, the process of filming, editing and publishing your own film about your research as a scientist can be a great creative outlet and quite rewarding. There is no room for creativity in science, or showing your personality through publications, however film is another story.

Waterlust, an organization I help run along with a couple other graduate students, is focused on creating these online based films in order to inspire more people to care about our environment. We mix the science and conservation in with sports such as freediving, kiteboarding, and sailing in order to pull more people in that wouldn’t otherwise seek out the science themselves. Taking this route we believe we’re able to reach more people that don’t already care, and hopefully get them to consider their own connection with the ocean, what water means to them, and educate them about issues facing our marine environment in order to inspire respect for these resources. This particular strategy is called entertainment-education (Singhal & Rogers, 1999). At Waterlust we often advocate for scientists becoming their own filmmakers, however collaborations between scientists and filmmakers can also result in successful ways in which to connect research with the public. The point is to get the information out there through an engaging, effective medium: film.

It’s important to note that I’m not at all suggesting that film will ever replace peer reviewed articles in scientific journals, only that it is a great supplement to said publications. In fact, a major barrier to film becoming a more mainstream way in which to communicate science is that it is not peer reviewed. With regards to this, it is important to maintain integrity and stick to true, science based information. That said, film is definitely gaining traction within the scientific world. Support for film is seen through contests such as Ocean180, sponsored by the Florida Center for Ocean Sciences Education Excellence (COSEE Florida), and NSF’s video contest. Video abstracts accompanying papers are becoming more popular, and many scientists are recognizing its value for broader impacts.

REFERENCES

Showstack, R. (2013), Ocean Science Video Challenge Aims to Improve Science Communication, Eos Trans. AGU, 94(40), 351.

Singhal A, Rogers E.M. (1999), Entertainment–education: a communication strategy for social change. Lawrence Erlbaum Associates, Mahwah, NJ

Impact of Costa Rican Longline Fishery on its Bycatch Species

October 28, 2013/1 Comment/in Conservation, Ocean News /by aanstett

by Fiona Graham, RJD Graduate Student and Intern

Bycatch, the incidental catch of non-target species, tends to be high when using non-discriminatory fishing methods, such as longlining. Longline fisheries, such as that of Costa Rica, generally target mahi mahi and silky sharks, however data collected by an observer program shows that a large percentage of their catch is olive ridley turtles and non-target shark species. These longlines literally consist of long lines of baited hooks that stretch for miles and soak in the water for hours. Unfortunately, fisheries bycatch is one of the primary reasons for population declines in sharks, rays and sea turtles. This is due to their life history characteristics, such as long lifespans, late age of maturity, and few offspring, that make them inherently sensitive to these high rates of mortality.

In a recent paper describing the impact of the Costa Rican longline fishery on its bycatch species, authors Derek Dapp et al. examine the catch numbers, capture locations, seasonality and body size of non-target sharks, sting rays, bony fish and olive ridley turtles. The paper uses data from the fishery observer program from 1999 to 2010 where observations were conducted onboard six medium scale vessels out of a Costa Rican fleet of 350 vessels. One troubling, but not so surprising result of their analysis found that the olive ridley turtle was the second most abundant species captured by the fishery. Two of the six major beach nesting aggregations for olive ridleys in the world are in Costa Rica, and populations at these two main nesting beaches have declined since the 1980s. Based on (most likely an underestimate) of the number of olive ridleys caught by the fishery – 290,500 a year – the impact of the Costa Rican longline fishery on olive ridleys needs to be greatly reduced.

Olive ridley sea turtle (photo: Wikimedia Commons).

Large numbers of sharks and rays are also caught as bycatch by the longline fishery, where rays are thrown back overboard and sharks are retained for their fins, meat, or as bait. Notably, the authors were able to identify a blacktip nursery near the Osa Peninsula due to the presence of high catch rates of juvenile blacktip sharks during the spring and summer months.

Catch per 1000 hooks on longlines for blacktip sharks, indicating the presence of a nursery ground near the Osa Peninsula (figure: Dapp et al. 2013).

As well as affecting blacktip sharks, the authors found that the fishery affected the other two species of shark that they examined, silky sharks and pelagic thresher sharks. They concluded that there is a clear need for more effective management of the Costa Rican fishery.

While this is an obvious conclusion to be made here based on the data available, the specific management protocol and how that management is put into place and enforced is a more complicated discussion. In this recent paper, Dapp et al. criticize many fisheries biologists for believing that the only acceptable methods of reducing bycatch are those that do not inconvenience fisherman or reduce their target catch substantially. They conclude that the only solution is through reduction of fishing effort through creation of marine protected areas or time area closures. They also suggest placing observers on at least 50% of medium and larger fishing vessels to acquire more data on fishing methods and bycatch and to educate fishermen to improve their techniques and to release bycatch species alive.