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BP Disaster Recovery Through the Lens of the Exxon Valdez Oil Spill
The first and second phases of the BP trial involving the Deepwater Horizon oil disaster are behind us. The judge is now deciding how to rule on the issues of gross negligence and amount of oil released into the ocean, while a third and final phase is set for Jan. 2015. Yet, while the end of the courtroom drama is in sight, the genie BP let out of the bottle almost four years ago has not gone away, and questions abound. For example, how is lingering oil affecting the food web? Which impacts will remain hidden? And how long will recovery of the environment take? Answers to these questions are frustratingly elusive, especially since the results of government studies assessing environmental damage are still mostly confidential.
With the fourth anniversary of the BP disaster nearly upon us, we can look back to the March 1989 Exxon Valdez oil spill in Alaska for insight into the types of impacts seen four years after that oil spill and what they might mean for Gulf recovery. As Alaskans reach a significant milestone today—the 25th anniversary of the Exxon Valdez disaster—the successes and setbacks in coastal Alaska’s recovery are instructive. These insights put the Gulf’s recovery into perspective and tell us that science is the foundation of a decades-long restoration effort, and it must not be shortchanged.
Four years after the tanker Exxon Valdez belched 11 million gallons of oil into Prince William Sound, the water’s surface was largely oil-free. However, patches of asphalt-like deposits remained on area beaches and pockets of relatively “fresh” oil could be found below the surface. Residual BP oil persists, embedded in marshes, beaches and offshore sediments. When disturbed, as was the case following Tropical Storm Karen, it re-oils sensitive habitats. Lingering oil poses risks to the species and can slow recovery, either through direct re-exposure or indirectly through ingestion of contaminated prey. To this day, lingering Exxon Valdez oil is monitored on sheltered beaches in the Gulf of Alaska. The Gulf of Mexico needs a similar long-term monitoring effort to track remaining reservoirs of submerged BP oil and its food web impacts.
Finfish Exposure and Recovery
Salmon are the most important finfish, culturally and commercially, to Alaskans. Oil from the Exxon Valdez reached about one-third of pink salmon streams in Prince William Sound. Repeated exposure of fish eggs to relatively less toxic oil slowed the recovery of pink salmon, which was not declared recovered until 1998. Another species, Pacific herring, which once supported a multimillion-dollar fishery in Prince William Sound, was another casualty of Exxon Valdez oil. In 1993, the Prince William Sound herring population crashed, the result of a perfect storm of natural and man-made factors, including Exxon Valdez oil. More than 20 years later, Pacific herring still has not recovered and is the focus of ongoing studies.
In the Gulf of Mexico, fisheries are a $5.7 billion industry. Much is still unknown about the impacts of the BP disaster on finfish or what ripple effects these might have in the ecosystem or fisheries, but new research findings give us a glimpse. Scientists found that when young bluefin tuna were exposed to crude oil from BP’s ruptured wellhead, their hearts were at greater risk of malfunctioning. The BP disaster occurred at the time bluefin were spawning, so it is possible the 2010 class took a hit. Menhaden is also a significant wild card because it is so critical to the Gulf food web. The distribution of this forage fish overlapped with the BP oil spill footprint, but scientists don’t yet know—or aren’t saying—to what degree the species was affected.
Now is the time to model best and worst case oil spill impact scenarios for finfish species of concern, like bluefin or menhaden, using the results to guide recovery strategies and help fishermen plan ahead. Long-term studies for exposed finfish similar to those for Pacific herring in Alaska are also needed.
Wildlife Exposure and Recovery
An estimated 250,000 birds were killed by the Exxon Valdez disaster. Several populations of birds, including bald eagles, had recovered by 1994, but many of those in oiled areas had not. Harbor seals may have declined by as much as 300 individuals following the disaster, continuing a declining trend first observed in 1984. Two pods of killer whales occurring in waters exposed to Exxon Valdez oil lost a combined 22 animals between 1989 and 1994, and neither pod had recovered by 1994. Many of these species have been the focus of oil spill impact studies dating back to 1989, with surveys continuing today because populations have not fully recovered.
In the Gulf of Mexico, thousands of birds representing about 100 species were recovered from the BP disaster impact area. In actuality, the total number is likely many times higher because carcasses are eaten, sink or drift away. Since the disaster, hundreds of sea turtles and bottlenose dolphins have stranded. The dolphin die-off is the longest and worst ever seen in the Gulf. We need to get to the bottom of dolphin deaths to not only arrest the trend if we can and aid their recovery, but also to determine whether conditions for dolphins in the Gulf are changing and why. Scientists need to collect data over many years in order to detect trends and understand ecological relationships. For this reason, long-term health assessments for wildlife species impacted by the BP disaster are high priorities for restoration and gauging recovery.
Recovery Is a Marathon, Not a Sprint
The Exxon Valdez experience taught us that recovery from oil spills can be two steps forward and one step back. Oil spill restoration is like a marathon; the process is long and pacing matters. The best way to prepare for the long haul and make periodic course corrections is to learn as much about oil spill impacts and ecosystem drivers as solid science will tell us, and respond accordingly. Tracking the health of an ever-changing Gulf is as important for restoration as regular checkups are for people, even more so for those recovering from an illness. Without a finger on the Gulf’s pulse and understanding how changes in this body of water affect recovering species, the right diagnosis or decisions about this or that species cannot be made. We need dedicated Gulf-wide monitoring for a minimum of 25 years to track recovery from the BP disaster. If there is one lesson we have learned from the Exxon Valdez disaster, it is that good science is the glove that fits around the hand of restoration.
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Farms with just one or a handful of different crops encourage fewer species of pollinating and pest-controlling insects to linger, ultimately winnowing away crop yields, according to a new study.
Up to half of the detrimental impacts of the "landscape simplification" that monocropping entails come as a result of a diminished mix of ecosystem service-providing insects, a team of scientists reported Oct. 16 in the journal Science Advances.
Monocrop palm oil plantation Honduras.
SHARE Foundation / Flickr / CC BY-NC 2.0
"Our study shows that biodiversity is essential to ensure the provision of ecosystem services and to maintain a high and stable agricultural production," Matteo Dainese, the study's lead author and a biologist at Eurac Research in Bolzano, Italy, said in a statement.
It stands to reason that, with declines in the sheer numbers of insects that ferry pollen from plant to plant and keep crop-eating pests under control, these services will wane as well. But until now, it hasn't been clear how monocultures affect the number and mix of these species or how crop yields might change as a result.
Aiming to solve these questions, Dainese and his colleagues pulled together data from 89 studies cutting across a variety of landscapes, from the tropics of Asia and Africa to the higher latitudes of northern Europe. They tabulated the number of pollinating and pest-controlling insects at these sites — both the absolute number of individuals and the number of species — along with an assessment of the ecosystem services the insects provided.
In almost all of the studies they looked at, the team found that a more diverse pool of these species translated into more pollination and greater pest control. They also showed that simplified landscapes supported fewer species of service-providing insects, which ultimately led to lower crop yields.
The researchers also looked at a third measure of the makeup of insect populations — what they called "evenness." In natural ecosystems, a handful of dominant species with many more individuals typically live alongside a higher number of rarer species. The team found as landscapes became less diverse, dominant species numbers dwindled and rare species gained ground. This resulting, more equitable mix led to less pollination (though it didn't end up affecting pest control).
"Our study provides strong empirical support for the potential benefits of new pathways to sustainable agriculture that aim to reconcile the protection of biodiversity and the production of food for increasing human populations," Ingolf Steffan-Dewenter, one of the study's authors and an animal ecologist at the University of Würzburg in Germany, said in the statement.
The scientists figure that the richness of pollinator species explains around a third of the harmful impacts of less diverse landscapes, while the richness of pest-controlling species accounts for about half of the same measure. In their view, the results of their research point to the need to protect biodiversity on and around crops in an uncertain future.
"Under future conditions with ongoing global change and more frequent extreme climate events, the value of farmland biodiversity ensuring resilience against environmental disturbances will become even more important," Steffan-Dewenter said.
Reposted with permission from our media associate Mongabay.
Ivory Coast's rainforests have been decimated by cocoa production and what is left is put in peril by a new law that will remove legal protections for thousands of square miles of forests, according to The Guardian.
By Karin Kirk
Greenland had quite the summer. It rose from peaceful obscurity to global headliner as ice melted so swiftly and massively that many were left grasping for adjectives. Then, Greenland's profile was further boosted, albeit not to its delight, when President Trump expressed interest in buying it, only to be summarily dismissed by the Danish prime minister.
During that time I happened to be in East Greenland, both as an observer of the stark effects of climate change and as a witness to local dialogue about presidential real estate aspirations, polar bear migrations and Greenland's sudden emergence as a trending topic.
Heavy metals that may damage a developing brain are present in 95 percent of baby foods on the market. Cirou Frederic / PhotoAlto Agency RF Collections / Getty Images
Heavy metals that may damage a developing brain are present in 95 percent of baby foods on the market, according to new research from the advocacy organization Healthy Babies Bright Futures (HBBF), which bills itself as an alliance of scientists, nonprofit organizations and donors trying to reduce exposures to neurotoxic chemicals during the first three years of development.
By Kerstin Palme
Creepy-crawlies are among the oldest life forms on this planet. Before dinosaurs ever walked the earth, insects were certainly already there. Some estimates date their origins to 400 million years ago. They're also extremely successful. Of the 7 to 8 million species documented on Earth, around three quarters are likely bugs.
But several insect species could disappear for good in the next few decades and that would have serious consequences for humans.
Volvo introduced its first-ever all-electric vehicle this week, kicking off an ambitious plan to slash emissions and phase out solely gas-powered vehicles starting this year.
The report, released Wednesday, found that almost every European who lives in a city is exposed to unhealthy air, Reuters reported.