The Blog Aquatic » Alexis Baldera News, opinions, photos and facts from Ocean Conservancy Tue, 12 Aug 2014 18:48:05 +0000 en-US hourly 1 Interview: Deep-Sea Researcher Dr. Samantha Joye on Microbes in the Gulf Wed, 06 Aug 2014 13:29:13 +0000 Alexis Baldera

Dr. Samantha Joye aboard the research vessel Atlantis with the submersible Alvin in the background. Credit: Antonia Juhasz

This blog is part of a series of interviews with scientists who are championing marine research in the Gulf of Mexico.

Dr. Samantha Joye is a Professor of Marine Sciences in the University of Georgia in Athens, Georgia. She is an expert in biogeochemistry and microbial ecology and works in open-ocean, deep-sea and coastal ecosystems. Her work is interdisciplinary, bridging the fields of chemistry, microbiology and geology. Following the BP Deepwater Horizon oil disaster, Dr. Joye joined a team of scientists in the Gulf, investigating oil plumes from the disaster in the open ocean of the Gulf, which at the time BP claimed did not exist. Her team’s discoveries proved that there was more oil and gas in the water than BP and government agencies had predicted. She continues to study the impacts of the BP oil disaster, as well as the ecological processes at natural oil and gas seeps in the Gulf, Arctic Ocean and in the Guaymas Basin.

OC: How long have you been conducting research in the Gulf of Mexico, and what are your current research interests?

Dr. Joye: I embarked on my first Gulf of Mexico cruise in 1994, and I did my first submersible dive on that cruise. I was completely enthralled and totally hooked on deep-water exploration from that instant. I began working in the Gulf in earnest when I joined the faculty at Texas A&M University (College Station) in 1995. I have been working in the Gulf since that time. My research interests include understanding the environmental and physiological factors that regulate microbial hydrocarbon degradation in the Gulf’s waters and in both shallow (upper meter) and deep (>5 meters) sediments. We are interested in the cycling of a wide spectrum of hydrocarbons, ranging from methane to polycyclic aromatic hydrocarbons. We are also interested in the metabolic potential and capacity for hydrocarbon degradation (i.e., determining which microorganisms are there naturally, their abundance, and how fast and how well do they respond to large hydrocarbon infusions like that resulting from the Deepwater Horizon disaster).

OC: Here at the Ocean Conservancy offices, we have been following the deep-sea expeditions in the Gulf this summer, watching the live feeds, and listening to the scientists discuss what they are seeing. We would love to hear more about these cruises from you. What types of information have you been collecting? What have you learned on the cruises?

Dr. Joye: Our cruise in April 2014 was on board the R/V Atlantis. It was the first official research cruise using the newly renovated human occupied vehicle, Alvin, which was very exciting for us. The goal of this particular cruise was to visit and sample sites impacted by the Macondo blowout and to sample two types of very salty seafloor ecosystems called brines. Seawater is salty; it contains about 35 grams of salt per liter. However, in some places, super-salty brine fluids occur. Brines are defined as fluids containing more than 50 grams of salt per liter but some deep sea brines contain almost 10 times the amount of salt as seawater. Our saltiest site contained about 340 grams of salt per liter. We are studying two types of brines: those derived from ancient salt dissolution (which contain mainly sodium and chlorine and are sulfate-free) and those derived from gas hydrate formation (which are basically concentrated seawater and thus contain sulfate)

Our research cruises are intense; we conduct operations around the clock. Alvin operations occur between 8a.m. and 5p.m., and starting around 6p.m., we collect water and deeper sediment samples through the night. We also do geophysical surveys at night and during transits between sites to search for interesting seafloor geological features and gas and oil plumes. Being an oceanographer requires that you are able to thrive in this intense environment, where sleep is a luxury and where focused, hard work is required around the clock. It’s worth it because each dive presents an opportunity for discovery, and discovery is what it’s all about!

On our April cruise, we discovered some amazing things that we will be reporting in our science blog and in publications during the coming months. But first, a lot more hard work is required in the lab to process all of the sediment, water and brine fluid samples we collected on the ship. Cruises are intense, but it does not stop there. Post-cruise analyses and experiments keep us busy for often six to eight months. Then the phase of manuscript preparation and publication begins.

OC: Some people may not realize that as much as 16 million gallons of oil naturally seeps from the Gulf seafloor each year. How does that compare to the oil and gas that was released by the BP oil disaster?

Dr. Joye: Natural seeps are in no way similar to the Deepwater Horizon discharge, which released almost 210 million gallons of oil from a focused source (the wellhead) over the course of 84 days. Natural seepage releases about 0.04 million gallons a day over the entire Gulf of Mexico, while the Deepwater Horizon discharge released 2.5 million gallons a day in a localized area. If you compare the discharge per area released during the Deepwater Horizon disaster, the blown out well discharged orders of magnitude more oil than natural seepage. This was an unprecedented perturbation that led to a large number of unanticipated phenomena and impacts to the Gulf ecosystem even hundreds of kilometers from the discharging wellhead. The chronic impacts of this perturbation are only now coming to light.

OC: Considering that there are natural petroleum seeps in the Gulf, does this lessen the impacts of the BP oil disaster?

Dr. Joye: Absolutely not. Many people argue that since the Gulf is a site of extensive natural hydrocarbon seepage, a large discharge such as the Deepwater Horizon disaster would have little effect on the system. The implicit assumption here is that the system was primed and poised to respond to hydrocarbon inputs because the waters are exposed routinely to hydrocarbons. But this argument has several shortcomings. First, what this assumption neglects to consider is that the offshore Gulf is a blue water system, where the nutrients that fuel microbial growth are sparse and fiercely competed for. Oil and gas oxidizing bacteria require nutrients to build biomass and increase metabolic rates. Nutrient availability may well have limited the degradation of Deepwater Horizon oil and gas significantly. Second, natural seepage inputs are sparse and diffuse so the populations of microbes that eat oil and gas during normal conditions are, in fact, rare. They can respond rapidly, but as has recently been shown, they are often not able to sustain high rates of hydrocarbon consumption. So, how much of the Deepwater Horizon hydrocarbons were consumed by bacteria? I don’t think we know for sure, but I have done some simple back of the envelope calculations of nutrient demands by hydrocarbon degraders, and the results suggest it would be difficult to consume all of the discharged hydrocarbons given the nutrient pool available.

OC: Can you describe what a cold-seep community is and how the BP oil disaster might have affected those in the Gulf?

Dr. Joye: Natural hydrocarbon seeps are magical systems that evolve and change over time. The biological diversity of these environments – which is fueled by oil and gas degradation, driven by the activity of indigenous hydrocarbon-degrading bacteria – is astonishing. I remember vividly my first dive to the Gulf seafloor in a submersible in 1994. When the lights came on and I saw all the odd and amazing organisms living on oil and gas, I was simply shocked. My jaw was on the floor and I knew I wanted to study these incredible systems for the rest of my career, because they are fascinating and because we know so little about what makes them tick.

Natural seep habitats, especially deep-water coral communities which are the “old growth forest” analog of the seep evolution sequence, were impacted by the Deepwater Horizon oil plume and by weathered oil-containing marine snow, or tiny bits of organic matter that sink down from the surface to the seabed. Dispersants may well have also impacted the organisms at natural seeps, but many more experiments are needed to verify this hypothesis.

OC: A few of your recently published papers have focused on the fate of dispersants in the Gulf, and the impacts of the BP oil disaster on open-ocean ecosystems in the Gulf. Can you tell us more about your research on these topics?

Dr. Joye: Dispersants are complex chemical mixtures that act to break up oil and presumably make it small enough for microorganisms to eat. However, the literature on this is split: few studies show increased hydrocarbon biodegradation after dispersant application, and many show no effect or a negative effect on biodegradation. The Deepwater Horizon dispersant application was made after much scientific discussion and debate. The dispersants were applied to keep oil from reaching the coastline, and the potential impacts on open-water organisms, from microorganisms to fish to sharks, were not known. We still do not know conclusively how dispersants impact microorganisms, but what we do know is that it affects different microorganisms in substantially distinct ways. We need to know a lot more, and we are working diligently to obtain this information by doing detailed experiments in the laboratory. So the jury is out on whether dispersants increase hydrocarbon degradation and on how they impact the structure and function of the hydrocarbon-degrading bacterial communities that they are supposed to stimulate.

OC: During your deep-sea expeditions in the Gulf, have you found significant differences between oiled sites and non-oiled sites, or differences at the same site before and after oil exposure?

Dr. Joye: Both. We had been studying one site, Mississippi Canyon 118, for about five years prior to the oil spill, so we had a very good baseline there. The microbiology and geochemistry of the water column and sediments changed after the discharge. If you compare an oiled site to a non-oiled site, you also see striking differences, irrespective if you are at a ‘control site’ or a natural seep. The oiled sites are distinct in terms of microbiology and geochemistry. The differences are significant and prominent.

OC: How might these impacts affect the larger Gulf ecosystem and food web?

Dr. Joye: The Gulf’s food web starts at the top, and the key there is nutrients. A key question is how much of the nutrient inventory was taken up by oil-degrading bacteria and how much of that sunk to the bottom. It will take a very, very long time to return those nutrients from the seafloor up to the surface where phytoplankton can again incorporate them into the food web from zooplankton to small fish and ultimately big game fish and whales. Food web impacts often take 5-10 years to materialize (i.e., to be quantifiable) because it takes a while to start catching the fish from the 2010 year-class. Other considerations include the impact of oil and dispersant exposure on larval fish; that will also take a long time (5-10 years) to become quantifiable. Finally, there is the consideration of oil and dispersant exposure on adult fish and their health. A recent study by Dr. Steve Murawski at the University of South Florida showed that fish caught recently contained Deepwater Horizon polycyclic aromatic hydrocarbons in their livers. So the food web impacts from the Deepwater Horizon incident are poorly understood and will take years more of research to fully unravel and understand.

OC: Looking forward to the restoration process, it is clear we didn’t have a good baseline understanding of some of the habitats in the Gulf before the BP oil disaster. How will we know when they are recovered? What are realistic goals for restoration of some of these areas, such as deep-sea and open-ocean ecosystems?

Dr. Joye: Baselines are essential when it comes to evaluating environmental impacts. It is clear that not enough funds have been invested in developing baselines for microbial communities in the open water and seafloor of the Gulf. This is both surprising and disappointing, given the industrial presence in the Gulf. I believe it is in the best interest of the oil and gas industry to devote substantial resources into developing collaborations between industry and academic scientists to obtain such baseline data. What would this require: instrumentation, monitoring platforms, access to research vessels and interested scientists on both sides. I believe all of the required parts are there; the missing piece of the puzzle is funding. Given the amount of money generated by the oil and gas industry in the Gulf, the funding required to generate environmental baselines for the system would be small potatoes (relative to oil company profits), but the value of these baseline data would be immense.

Because we do not know the baseline, it is extremely difficult to judge when the system is recovered. We don’t even know if it will recover to the “baseline”. It could end up at a new steady state.

But there is satellite data that can be use that to evaluate how chlorophyll has changed since the oil disaster and those data can be used to describe pre- and post-spill carbon fixation scenarios. So, it is easier to evaluate the status of the open-ocean system compared to the seafloor system because deep-water corals, for example, grow very slowly. When a 500-year-old coral is damaged or killed by oiling, it will require a very long follow up study to evaluate recovery of that system.

Restoration of these systems is essentially impossible; what we can do is monitor recovery and attempt to understand what regulates its efficacy. That is the goal that many of us are working towards.

OC: It has been over four years since the BP oil disaster – what is the status of the ongoing research in your area of expertise? Are you as far along as you and your fellow researchers hoped to be by this point?

Dr. Joye: I am a microbial geochemist. Basically, that means I study the effects of microbial processes on elemental cycles. The Deepwater Horizon discharge served, in essence, as a tragic experiment. Tragic because eleven people lost their lives, and thousands more lost their livelihoods and an experiment because we have never had a marine oil disaster of this scale in U.S. waters. As far as microbial research goes, we have learned a great deal from it and we’ve had quite a few surprises and some interesting debates along the way. We’ve also realized how much we do not know.

Every research cruise we go on, every experiment we do, every time I simply sit in my office and ponder what I’ve seen and what my group and our collaborators have done, these things lead to additional questions that require further observation and experimentation. That’s how science works. Science is not static, and there is no end to it. There is always more work to do, more things to learn, more discovery and more excitement. I feel like we have made a tremendous amount of progress, but we have so much more to do and so much more to learn. In my opinion, we have only now begun to scratch the surface and dig into the details that drive many of the patterns observed during the discharge.

Honestly, I had no idea where we would be four years out because I did not know where the initial studies would lead us, but they have led us to very fruitful ground that will keep us busy for decades, funding permitting.

OC: What research remains to be done in the Gulf? What are the most important gaps we need to fill for research in the deep-sea, open-ocean or other ecosystems you study in the Gulf of Mexico? How can we fill those gaps?

Dr. Joye: The microorganisms that call the ocean home have enormous metabolic potential and, when exposed to perturbations, it is almost certain that some microorganisms are sentinels that could alert us to changes that are occurring in their environment. There are numerous data gaps – we know so little about the physiology of the billions of microorganisms that are present in a few drops of seawater. What are the dominant organisms and how do they respond to perturbation? What about the rare organisms? Who are they and how do they respond to perturbation? We have to understand the language of microorganisms – their language is spoken in terms of their diversity, physiological capacity and ability to tolerate or adapt to perturbation. We have to understand these three things to know what they are telling us when a perturbation occurs, whether that perturbation is a hurricane, ocean acidification or an oil discharge.

But this is my dream – to develop long-term microbial observatories in the Gulf and elsewhere. When I look at what one long-term ocean observatory site has taught us, Station ALOHA off of the island of Oahu in Hawaii, I know that this is a dream that I simply must make come true.

OC: Thanks for your time Dr. Joye! It has been a pleasure chatting with you and we look forward to hearing more about your future research.

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Fishermen and Scientists Work Together to Track Sick Fish Mon, 21 Jul 2014 14:22:59 +0000 Alexis Baldera

University of South Florida Professor Steven Murawski began studying diseases in fin fishes after the 2010 Deepwater Horizon oil spill when Gulf of Mexico fishermen began reporting a surge in fish with visible lesions. Credit: C-Image. Caption from

Fishermen are on the water every day, which means they are often the first to notice when something changes. After the BP Deepwater Horizon oil disaster, we heard reports from fishermen that they were catching more fish with lesions than they had ever seen before. Immediately after hearing these reports, Dr. Jim Cowan at LSU began investigating the frequency, location and cause of the reported lesions. Many other scientists have collected data on this same issue, and last week a group from the University of South Florida published the first round of results in a scientific journal.

Through extensive study, the scientists ruled out other potential causes, such as pathogens or oceanographic conditions, and concluded that the BP oil disaster is the likely cause of the fish lesions. Oil has a distinct chemical signature that allows scientists to differentiate between different origins, and contamination in the sick fish was a better match to oil from BP’s Macondo well than any other source.

For the Gulf, studies that help us understand the lingering impacts of the BP oil disaster are critical to achieving recovery. They are also a reminder that we cannot close the door on studying the effects of the disaster or the impact of our restoration efforts until we are certain the job is complete. The results of the USF study are only the beginning of this story about how fish were impacted by the BP oil disaster. In order to achieve complete recovery, we need long-term research on how lesions and other oil impacts affect the survival and reproduction of fish, how their populations are responding to habitat and water quality restoration efforts, and what that means for the fishermen who first identified the problem.

Location of sampling stations and the percent of skin lesions per station for June–August 2011. The percent of skin lesions at a station is indicated as follows: white circles = 0%, red graduated circles = 0.1–2.0%, 2.1–4.0%, 4.1–6.0%, and >6.0% (from smallest to largest). The gray shading is the cumulative distribution of surface oil occurring during the duration of the Deepwater Horizon (DWH) event. Map credit: Murawski et al., 2014

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800,000 and Counting: The Soaring Deepwater Horizon Bird Death Count Thu, 22 May 2014 18:21:58 +0000 Alexis Baldera
According to a new study, scientists estimate that between 600,000 and 800,000 coastal seabirds died because of the BP Deepwater Horizon oil disaster, a number far greater than any previous estimate. Understanding the ripple effect of 800,000 coastal birds dying in the Gulf of Mexico is critical to the recovery of this special place. These findings come from a study to be released this summer in Marine Ecology Progress Series, which was recently reported in the New York Times.

This new estimate for bird deaths in the Gulf is unprecedented for an oil disaster. For context, the estimate of dead birds following the Exxon Valdez Oil Spill was around 300,000.

What are the ecosystem effects of 800,000 birds dying?

In response to the study results, BP has released statements refuting the methodology and objectivity of the authors. Many of the studies that BP cites as counter arguments have not been shared with the public, and as far as we know, have not been peer reviewed. BP’s veil of confidentiality prevents the public from understanding their methodology and results. This is an obvious double standard, and we must ask ourselves:  who has more to gain from discrediting these findings and underestimating bird mortality than BP?

In order to increase transparency and have an accurate discussion about how to best estimate bird mortality or other impacts, it is necessary for all of the data and methods be on the table. This is critical information that managers and scientists need in order to know the full extent of the injury. And BP is blocking this information because they’re in the middle of a legal battle over the oil disaster.

The bird death  study comes at a time when BP is refusing to pay for key science critical to fully understanding the effects of the disaster on natural resources. This science is part of a series of ongoing studies under the Natural Resource Damage Assessment (NRDA) that BP previously funded. The fact that they are refusing to pay for this science at a time when some NRDA studies are underway, is telling. It is imperative that BP fund ongoing and future NRDA studies. These studies, required by the Oil Pollution Act of 1990, are designed to assess the extent of injury to natural resources and the subsequent restoration needed to compensate for that injury. Trustee agencies carry out NRDA studies, but the responsible party—in this case BP—is required to pay for them.

As the authors of the new study indicate, it is very likely that even this new examination of bird deaths underestimates the true number of birds killed by the disaster. For example, birds living in the coastal marshes or past 40 kilometers from shore (what scientists call offshore pelagic birds) are not included in the total. The range of impacts estimated in this new study contributes to our evolving understanding of what should be done to restore injured bird populations. Ocean Conservancy is focused not only on tracking the best available science to determine the full impact of the BP oil disaster, but also how we can restore the Gulf’s marine and coastal environments. There are opportunities to use innovative technologies to monitor and restore bird populations in the Gulf. We’ll explore these solutions in a future blog.

To view where some of the coastal seabirds make their home in the Gulf, our Marine and Coastal Atlas has maps of the northern gannet, brown pelican and royal tern.

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Interview with Marine Mammal Researcher Dr. Ruth H. Carmichael on the Stranding of Dolphins, Manatees and Whales Tue, 15 Apr 2014 13:50:57 +0000 Alexis Baldera

This blog is part of a series of interviews with scientists who are championing marine research in the Gulf of Mexico.

We know there was a very significant increase in the number of marine mammal strandings observed following the BP Deepwater Horizon oil disaster. Dr. Ruth H. Carmichael talks to Ocean Conservancy about her work to respond to strandings when they occur, collect data to better understand these strandings and put together public outreach programs to prevent them in the future.

Dr. Ruth H. Carmichael is the senior marine scientist at the Dauphin Island Sea Lab and associate professor of marine sciences at the University of South Alabama. Her research seeks to better understand the biological and physiological responses of organisms to environmental change. She also studies how nutrient enrichment and pollution, coastal structures, climate change and harvest pressure affect coastal habitats and species. As the Alabama Marine Mammal Stranding Network coordinator, she serves as a first-responder for dolphins and other animals that get stranded on the Alabama coast.

Ocean Conservancy: Why do marine mammal strandings occur in the Gulf of Mexico?

Dr. Carmichael: Marine mammals strand for a variety of reasons, some natural and some influenced by people. Most often, in coastal Alabama, animals strand after death and the specific cause of death is unknown, but may be related to illness or disease, natural or man-made environmental stress, problems during calving, old age, or human interactions. NOAA’s National Marine Fisheries Service (NMFS) makes information on strandings available to the public.

OC: What exactly do marine scientists mean by the term “stranding,” and how historically extensive has this problem been in the Gulf?

Dr. C: Stranding refers to animals that wash ashore or are otherwise trapped or stuck in a location that is not normal or favorable for survival. This may occur when carcasses wash ashore after death or when animals are alive, such as dolphins ‘beaching’ or manatees orienting to a wastewater treatment plant outfall and failing to migrate when water temperatures turn cold.

OC: Can you talk specifically about dolphins and strandings, and what types of environmental conditions in the Gulf cause strandings?

Dr. C: In coastal Alabama the peak stranding period is usually in the spring, consistent with one of the two broad peaks in calving in our area. But strandings can and do occur year round. Since early 2010, the region has experienced an Unusual Mortality Event (UME), the cause of which has not been determined. Hence, relationships to overall conditions in the Gulf of Mexico ecosystem are hard to define. We know that timing and location of some strandings have been related to extreme cold events and an associated spring freshet in 2011. We also know from NOAA research that some animals have been in poorer body condition and experienced disease.

OC: As the Alabama Marine Mammal Stranding Network (ALMMSN) coordinator, you are the first call when someone reports a stranded animal. Tell us about your experience responding to those emergency calls.

Dr. C: Because the Alabama Marine Mammal Stranding network responds to all marine mammal strandings (cetaceans, such as dolphins and whales, as well as manatees), our response is divided based on federal oversight for these species.

I personally take all emergency calls for manatees in the states of Alabama and Mississippi that come into our 24-hour emergency hotline for strandings, sightings where the animal is still on site, and other issues of immediate concern. I then either respond directly, report the issue to enforcement if it involves harassment, or dispatch a team to respond depending on the nature of the call and the location of the event. In the case of manatee strandings, this usually means salvaging a carcass for necropsy the next day by a team of staff and volunteers. We have only had one known live manatee wash ashore in Alabama, and unfortunately that animal was in such poor condition that it could not survive transport. We do not hold or rehabilitate manatees.

For cetacean response, I have an excellent stranding coordinator, Noel Wingers, who takes all emergency calls for these species and makes decisions regarding direct response or dispatching a team, depending on the situation. In the case of cetaceans, which are under the northern Gulf of Mexico UME and managed a bit differently, response is also a bit different in terms of whether a carcass is salvaged or sampled and disposed of after necessary data are collected. For live cetacean strandings, in every case, we follow National Oceanic and Atmospheric Administration (NOAA) guidance regarding how animals are handled, transported and where they go for rehabilitation. The details are different for every case. We do not transport or rehabilitate cetaceans.

We also rely on assistance from municipal, county and state authorities to assist with moving and disposing carcasses in some cases, and we are very grateful for their support and cooperation.

OC: It has been four years since the BP Deepwater Horizon oil disaster began – what is the status of the ongoing research in your area of expertise? Are you as far along as you and your fellow researchers hoped to be by this point?

Dr. C: Since 2010, we have been unable to conduct any research on biological samples from stranded marine mammals. As the result of litigation over the UME, all samples taken from stranded marine mammals in the state of Alabama have been collected by NOAA. We don’t know when or if we will be able to retain samples or have previously collected samples returned to continue our regular program of diagnostic study.

OC: Is more work needed to establish clear baselines for healthy and sustainable populations of marine mammals in the Gulf? What still needs to be done? And how would you explain its significance to the public?

Dr. C: Yes, more data are needed to establish baselines. Very little research has been done on stranded marine mammals in the north central Gulf of Mexico, and Alabama in particular has been a ‘black hole’ for data. We have had inconsistent stranding response and data collection in the past. With the establishment of the ALMMSN at Dauphin Island Sea Lab we hope to provide continuous, consistent and scientifically rigorous data collection from stranded marine mammals to better and more rapidly define causes of death, define relationships between environmental variables and stranding patterns, and enhance survival of live stranded animals. A major need is funding to operate the ALMMSN and to train dedicated long-term personnel who will build capacity for future stranding response and research on marine mammals. The only way to ensure recovery and conservation of marine mammals throughout the region is to properly outfit and support operation of dedicated consistent stranding networks. We also require additional data on live animal populations in the region, including data on genetics, population structure, contaminant exposure, health and body condition, feeding dynamics, reproduction and interactions with other populations, among other basic ecological data that are not available for our area.

OC: There are many animals on the Gulf Coast that can get stranded in addition to dolphins, including whales, manatees, turtles and sea birds. Can you tell us more about the importance of these species and their role in the ecosystem?

Dr. C: Many of these species are threatened and endangered. All are part of our community heritage and the natural resources that make up a healthy Gulf of Mexico ecosystem. And many are sentinel or key species that reflect broader ecosystem health and function, with implications for commercial fisheries success and human health risks. They all also support local economies as part of a growing regional ecotourism industry.

OC: We know there was a very significant increase in the number of strandings observed following the BP Deepwater Horizon oil disaster. For example, 930 strandings were reported in the northern Gulf between February 2010 and April 2013. But these large numbers are just numbers to many people. Can you put these numbers in context? Has anything like this happened before?

Dr. C: Our stranding network is relatively new, but we can look at mean numbers of strandings reported historically in our area and make some comparisons. For example, in the past in Alabama (2007-2009) there were about a dozen strandings reported each year. During 2010-2013, numbers of strandings ranged from 25 to 60 animals each season. It is important to note that during historical periods, stranding response was sometimes inconsistent and we suspect strandings were under-reported, but this difference is still substantial, with at least two to five times more strandings after 2010.

OC: Given that strandings occurred before the BP oil disaster, are there patterns to the strandings that suggest causes other than exposure to oil? Your research with William M. Graham, Allen Aven, Graham Worthy and Stephen Howden suggests water temperature changes and unusual freshwater discharges may have played significant roles. The research also identified diet, nutrition and food web changes as likely contributing factors, correct?

Dr. C: Natural physical and chemical attributes of any system can affect when and where animals strand. These attributes interact with but do not preclude other factors that cause mortality. For example, a disease might result in mortality but the local water flow patterns may determine when and where the resulting carcasses wash ashore. Similarly, colder than usual temperature or exposure to oil related contaminants could affect the abundance, distribution and condition of prey species available as food for dolphins and other predators in affected areas. Altered food supply could, in turn, affect dolphin condition and susceptibility to disease or other stresses. Exposure to oil-derived substances could also directly affect the condition of animals in ways we don’t fully understand or have yet to discover. Hence, all of these factors can interact to directly, and indirectly, affect stranding dynamics.

OC: Lastly, why, after four years since the UME began, are the marine mammal stranding networks on the Gulf Coast still struggling to get the resources needed to carry out this important work?

Dr. C: I cannot answer for other networks, but in the case of the Alabama Marine Mammal Stranding Network at DISL, we are relatively new. It takes time to build a relationship with the public and with other stranding authorities, train personnel, and build infrastructure. We are very fortunate that we received support in our early months, during and just after the BP Deepwater Horizon oil disaster from NMFS and the National Fish & Wildlife Foundation for basic start-up equipment and response activities. We have excellent colleagues in the stranding network and the NMFS southeast region, who have helped train our personnel and answered many questions. The Alabama Department of Conservation and Natural Resources and the U.S. Fish & Wildlife Service have also been very supportive of our efforts.

It is also important to understand that all of the stranding networks in the Gulf of Mexico are over-extended in personnel time and other resources due to responding to the higher than usual number of strandings during the Gulf of Mexico UME. This has been the longest duration UME in Gulf history. As a result, most stranding networks remain in need of some additional support to maintain response quality and consistency. In Alabama, we have the added burden of beginning and institutionalizing a new program. This investment, however, is already paying off. Alabama now has a nearly four-year record of responding to 100 percent of marine mammal strandings reported in the state, providing mutual aid to neighboring networks, and performing full data collection, including biological sampling on 100 percent of the carcasses for which such data collection is appropriate. We are working hard to build stranding response capacity, to no longer be the ‘black hole’ for data in our region and to establish baselines needed to evaluate the BP Deepwater Horizon oil disaster, as well as prepare for, assess and respond to future catastrophic events.

OC: As an interesting side note, many folks in Alabama are probably familiar with the manatee license plates, stickers, and signs associated with the awareness program that you started in order to change people’s perception about Alabama’s resident manatees. Can you tell us about that outreach program, and what inspired you to start it?

Dr. C: We started our outreach campaign for manatee awareness in Alabama for two main reasons. First, we wanted to enlist the help of the public to learn more about when and where to find manatees in our area and to gather and analyze these publicly sourced data in a measurable way to support our subsequent research. Many Alabama and Mississippi residents are on the water regularly and have an opportunity to see these animals, but in the past, nobody was collecting and assimilating this information. We wanted to give the public a place to consistently report sightings in a specific way that would make them useful for us and other end users (including the public) to learn about manatee habits and habitat use. By reaching out to the public we could get them involved and functionally increase our knowledge about these animals and their movements in our area to support conservation.

Second, we wanted to use this program to share data back to the public and other authorities and let them know that manatees are here in local waters, and because of public participation in our research, we know more. We could then let local residents and policy makers know when and where to expect to find manatees in our area to guide boating practices, coastal project planning, habitat conservation and restoration activities. Our data combined with historical data we compiled allowed a change in classification of manatees from Accidental to Priority for conservation in our area now that we know these animals are regular at least seasonal visitors to our local northern Gulf of Mexico waters. Our data have also been useful to better understand home range of manatees throughout the Gulf of Mexico region between our local waters and Florida, which contributes to Gulf-wide resource conservation and management for this endangered species.

More from This Blog Series:

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Potential Threats from BP Oil to Bluefin and Yellowfin Tuna, Swordfish and Amberjack Tue, 08 Apr 2014 18:33:03 +0000 Alexis Baldera

© Cheryl Gerber

A new study published last month reveals how the 2010 BP Deepwater Horizon oil disaster likely caused life-threatening heart deformities and irregular function in the fish embryos of yellowfin tuna, bluefin tuna, amberjack and swordfish.

If you’re thinking that this sounds like another study we reported on last month, then you’re right. A number of different studies have been conducted on fish hearts, and each of them is an important piece of the puzzle that scientists are assembling to understand the impacts of the BP Deepwater Horizon oil disaster.

This latest study conducted by Dr. John Incardona and others clarifies how the oil from the BP oil disaster affects the embryos of large predatory fish living in the open ocean (or pelagic zone) of the Gulf of Mexico. Previous studies have determined that crude oil can be toxic or have delayed fatal effects on fish living in cold Arctic waters, such as pink salmon, or in warm freshwaters, such as zebrafish. We’ve also recently learned that Gulf killifish living in oiled areas of coastal Louisiana are suffering from deformed hearts and reduced chances of survival; another study helped us better understood the mechanism by which crude oil affects tuna hearts. Collectively, this research allowed scientists to make assumptions about how oil might affect fish living in the warm offshore waters of the Gulf.

These new findings draw a solid line between the crude oil released by the BP oil disaster and possible impacts to the pelagic fish spawning in the Gulf, meaning that the puzzle is coming together and fewer assumptions will need to be made about impacts. The implications for Gulf fish were summarized by the authors, who said that the “losses of early life stages were therefore likely for Gulf populations of tunas, amberjack, swordfish, billfish, and other large predators that spawned in oiled surface habitats.” Depending on how many fish eggs and larvae were killed or damaged as a result of oil exposure, a loss of these young life stages could translate to a reduction in the total population of impacted fish.

What I found most alarming in the study results was the low concentration of oil needed to cause irregular heart function. Using water quality data collected for the Natural Resources Damage Assessment, the authors estimated that 20 percent of the water samples collected in the pelagic spill area met this low threshold for oil contamination.

Other fish species such as king and Spanish mackerels, mahi mahi, sailfish, blue marlin and cobia were also spawning in the Gulf at the time of the BP oil disaster. All of these fish are crucially important to the Gulf ecosystem as top ocean predators and to the Gulf economy as valuable fisheries resources.

The total impact to the wild populations of tuna, amberjack and other large pelagic fish is yet to be determined, and is one of the reasons why it is critically important that we continue to research and monitor the impacts of the BP oil disaster throughout the ecosystem. We need more research to determine how experimental findings like those of Dr. John Incardona and others translate to the trends we are seeing in wild populations, and we need continued long-term monitoring to observe those trends and track how fish populations are changing.

The impacts of the BP oil disaster are still unfolding, and hundreds of studies are underway to determine the total impact. Ocean Conservancy continues to track this research, and we will continue to post updates on emerging impacts and trends.

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Interview: The Unfolding Story of BP Disaster’s Impact on Gulf Shrimp Thu, 13 Mar 2014 14:59:29 +0000 Alexis Baldera

Dr. Kim de Mutsert deploys a shrimp trawl to collect samples. [Photo: B. Bachman]

(This blog is part of a series of interviews with scientists who are championing marine research in the Gulf of Mexico.)

Shrimp are not just an integral part of the Gulf Coast’s culture and cuisine, but they are also a pillar of its economy. The impacts of the BP Deepwater Horizon oil disaster to this iconic animal are a great concern. Drs. Kim de Mutsert and Joris L. van der Ham of George Mason University study the oil’s effects on white and brown shrimp in the Gulf of Mexico. De Mutsert specializes in applied fish ecology, estuarine ecology and ecosystem modeling, including the effects of coastal restoration scenarios on fish, shrimp and oysters in Louisiana. Van der Ham, formerly a postdoctoral researcher at Louisiana State University, is an invertebrate zoologist who has investigated the effects of the BP disaster on inshore shrimp populations. We interviewed them about their research and what more needs to be done.

Ocean Conservancy:  The two of you have researched the effects of the BP Deepwater Horizon oil disaster on white and brown shrimp in the Gulf of Mexico. Could you briefly summarize your findings for us?

Drs. Kim de Mutsert and Joris L. van der Ham:  We compared the abundance and size of brown and white shrimp collected in estuaries that were heavily impacted by the spill with shrimp that were collected in estuaries that were minimally impacted by the spill. We found that both species of shrimp were more abundant in heavily impacted estuaries than in minimally impacted estuaries during the season following the spill. Size, however, did not differ between estuaries. This counterintuitive result could mean that the shrimp grew slower, which delayed the exodus of shrimp offshore to spawn. It could also simply be an effect of fishing closures, which were implemented after the oil spill in the more heavily impacted sites. Our study did not give us conclusive evidence on which of the two mechanisms was responsible.

OC:  The oil disaster began around the start of white shrimp spawning season, so the impact would have been noticed quickly. Was there an effect on other species throughout the Gulf ecosystem via the food web? Additionally, were there noticeable changes in the shrimp fisheries in the Gulf?

DM & VdH:  The increase in shrimp abundance will certainly have had an effect on the other species via the food web. If, however, this effect had any significant community-wide consequences remains unclear. Inshore shrimp fisheries were affected by the spill because of the fishing closures that were implemented immediately after the spill. Later, the media reported low catch rates in 2011, but we have not found any evidence of dramatically decreased abundances.

OC:  Shrimp return to the deep-water in the Gulf – where they can be eaten by reef fish, such as snapper and grouper – to spawn. Could the oil found in shrimp affect those fish?

DM & VdH:  There were many reports in 2011 and 2012 of shrimp with black branchial cavities (where their gills are located and through which water is circulated for respiration). If this is indeed oil, then that represents a possible source of toxicity for the fish that fed on those shrimp. It is not clear, however, how much this contributes to the compromised health of individual snapper and grouper compared to direct exposure to spilled oil offshore. In general though, vertebrate species are able to metabolize contaminants such as PAHs (polycyclic aromatic hydrocarbons) they ingest through food relatively quickly, so the direct exposure to oil (through the gills) is likely to play a larger role in higher trophic (feeding) level species [such as reef fish].

OC:  Tell us why problems in the growth rate or distribution of shrimp should be of concern.

DM & VdH:  It is important for shrimp to reach a large body size. Especially for females, the large body size ensures that the individual can store enough energetic reserves to produce a large number of offspring. Shrimp will start migrating offshore to mate and spawn when they reach a minimum threshold size. If their growth rate is not sufficiently fast, shrimp will delay their migration, and as a result a population may produce less offspring.

OC:  Can you give us a sense of the extent to which the Gulf’s food web, in which shrimp play such an integral part, has been affected by oil?

DM & VdH:  This is still hard to say, since organisms that have longer turnover times (lifespan) could suffer sublethal effects as a result of exposure to oil or reduced food availability that could lead to reductions in population size in the future. Examples of such sublethal effects are an impaired immune system or reduced fecundity [ability to reproduce].

OC:  Was there a historical baseline established for the health of Gulf shrimp populations prior to the BP Deepwater Horizon oil disaster?

DM & VdH:  Yes. The Louisiana Department of Wildlife and Fisheries (LDWF) has been conducting inshore monitoring studies that have included shrimp since the 1980s. In addition, the National Oceanic and Atmospheric Administration keeps track of fisheries landings data, including the Louisiana shrimp fisheries. Even though neither of these are direct measures of the health of shrimp populations, they do monitor the abundance of shrimp at inshore locations.

OC:  What research is still needed? Where are the gaps in our knowledge?

DM & VdH:  The sublethal effects of the oil spill on long-lived species are much harder to determine. The current state of the pollutants and the condition of higher trophic level organisms and how the oil affects their reproductive success could use continuous research. We also would have liked to carry out a study concurrent to our field study that focused on the physiological effects of oil and PAHs in shrimp, and the levels of these compounds in shrimp in the field. This would have helped us tease out cause-and-effect relationships that could provide invaluable information for future disasters. Unfortunately, we were unable to secure funding for those components.

OC:  What recommendations can we make to our policymakers to restore and protect Gulf shrimp and their habitat?

DM & VdH:  Keep track of shrimp abundance through monitoring projects such as those carried out by LDWF to determine every year when the start of the shrimp season should be and what the size of the stock is. A focus on the reduction of wetland loss is warranted in coastal restoration projects, as these estuaries are crucial to shrimp and other organisms that use these habitats. Because of the fast turnover time (lifespan) of shrimp, the population responds quickly to our actions. It is for example not unlikely that the fishing closures in response to the oil spill resulted in such a boost in shrimp abundance that negative effects of the spill were quickly resolved. Actions such as these can be applied in cases in which shrimp abundances decline for reasons that are either unknown or hard to solve.

Marsh edge, important habitat for juvenile shrimp, covered in oil from the BP Deepwater Horizon oil disaster in 2010 [Photo: Kim de Mutsert]

 More from This Blog Series:

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Interview: Dr. Paul Montagna on Deep-sea Impacts of the BP Oil Disaster Tue, 11 Feb 2014 13:06:59 +0000 Alexis Baldera

Dr. Paul Montagna

(This blog is part of a series of interviews with scientists who are championing marine research in the Gulf of Mexico.)

Most images related to the BP Deepwater Horizon oil disaster are of oil floating on the surface of the Gulf of Mexico or washing up on its shores, but what has happened in the deep-sea environment? Dr. Paul Montagna of Texas A&M University-Corpus Christi explores that question. In a recent publication in PLOS ONE, he estimated the size of the deep-sea “footprint” left behind by the BP Deepwater Horizon Macondo well blowout. He has documented severe impacts to bottom-dwelling animals over a 9-square-mile area (equivalent to 4,356 football fields) and moderate impacts within another 57 square miles, an area twice the size of Manhattan.

Ocean Conservancy: What do your findings tell us about impacts from the BP oil disaster?

Dr. Montagna: We discovered that oil did reach the bottom, and it did have a very large impact on the organisms that live on the bottom. We could identify a footprint of the oil spill. We saw increased hydrocarbons, increased metals associated with petroleum activity, and reduced diversity and abundance of some key indicator organisms.

OC:  What were the specific impacts to organisms?

Dr. M.:  The primary one that I focused on is about a 30 percent reduction in diversity in an area about 9 square miles around the blowout site. What that means is that the organisms that were sensitive just disappeared.

OC:  Do the impacts to the deep sea have impacts to the rest of the Gulf ecosystem?

Dr. M.:  Yes, the things that live on the bottom are very important for different reasons.

They serve as food for higher trophic (food chain) levels, particularly for fish and other organisms that come and feed on the bottom sediments.

Additionally, the deep sea is characterized as a depositional environment. In other words, material is constantly falling on the deep sea. The deep sea is very important in recycling organic matter and generating new nutrients.

Deep-sea organisms also play a role in carbon sequestration. In that regard, they are important for helping maintain the climate and productivity of the ocean in general.

OC:  How do your findings relate to other deep-sea impacts studies, for example those showing dead or dying coral near the Deepwater Horizon site?

Dr. M.:  The key is that both the coral studies and the sediment invertebrate studies that independent researchers have done both show that bottom-dwelling organisms were impacted by the spill.

Dying coral covered with oil (left) compared to a normal coral with some dead skeletal material covered by typical secondary colonization (right). [Photo: NOAA OER and BOEM]

OC:  What does recovery mean for this deep-sea environment?

Dr. M.:  One interesting thing about the deep sea is that it is uniformly cold. The entire deep sea is about the same temperature as a refrigerator, it is about 4 to 5 degrees Celsius [39 to 41 degrees Fahrenheit]. You know we put things in a refrigerator so they don’t degrade. Through my own past studies and other work, we know that metabolic rates in this environment are ridiculously slow, so I would imagine that any oil that wound up on the bottom is going to be around for quite a while. It is entirely possible for it to take a very, very long time for recovery to occur via natural degradation.

Another way the deep-sea environment could recover would be through deposition; in other words, the oil just gets naturally buried. That is something we definitely want to be able to look at in the future.

OC:  Are you still collecting samples?

Dr. M.:  We collected samples in June of 2011, and we’re working on those right now. They will tell us a little about change through time. We’re considering going back out in the summer of 2014.

OC:  Is there uniform coldness below a certain depth?

Dr. M.:  The depth doesn’t matter; it relates to the density. Seawater is most dense at about 4 degrees Celsius, so that is why that water sinks. And once it gets to the deepest parts of the ocean, it kind of just sits there.

OC:  How should we define the deep sea for this blog?

Dr. M.:  Two ways: In the Gulf of Mexico, it is below about 200 to 300 meters, or say, beyond the edge of the continental shelf. It might be best to include both descriptors because the shelf break occurs at different distances from shore and different depths in different places.

OC:  What can we do to restore, or compensate for injury in, the deep-sea benthic environment?

Dr. M.:  This has to be one of the most challenging things about the situation. We have never had an accident of this scale and scope in the deep sea before, and the deep sea is difficult to work in because it is largely inaccessible. There is a real concern about what we can and should do for restoration. Under the state and federal Natural Resource Damage Assessment laws and regulations and restoration planning process, we are required to restore natural resources. I’m not sure that the types and amounts of restoration have been determined yet. I think there are several possibilities.

One option would be primary restoration of resources in place. Another option is compensatory restoration in other places; in other words, do something somewhere else to try and mitigate impacts. The third alternative may be some habitat creation or restoration projects; it may be possible to create some artificial habitats offshore.

Since deposition will occur over time, it could be a matter of waiting. However, how long this will take I don’t know.

OC:  Do we also need additional research to help develop strategies and policies that can effectively promote and maintain the productivity and health of the Gulf ecosystems you study? What is highest on your list of research that still needs to be done? And how critical is this scientific work to the future of the Gulf and the communities that depend on it for their livelihoods.

Dr. M.:  Although deep-sea studies have been going on for many decades, we still don’t know some fundamental facts. Because it is so expensive to do deep-sea research, we haven’t sampled the same locations at different times, so we know little about how communities change over seasons, years or decades. Biodiversity of the deep-sea is large, yet we have identified very few of the species that are new to science. So, classical systematic studies are critical to improve our understanding of diversity.

There are still some unanswered questions in the shallow regions. Coastal restoration projects are an experimental manipulation of the environment, yet we seldom collect sufficient data after a project to learn from our experiences, so I think we should require extensive follow-up studies to improve our abilities to restore the coast.

I also have a concern about known biodiversity and productivity hot spots, such as areas where there are bottom features such as pinnacles and reefs.

The Gulf is “America’s Sea” with many, many users. There will always be competing interests, so we need a fuller understanding of the Gulf’s bounty and how to manage its resources to benefit future generations.

More from This Blog Series:

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