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This page includes news articles of international and national interest. Seagrass-Watch HQ does not guarantee, and accepts no legal liability whatsoever arising from or connected to, the accuracy, reliability, currency or completeness of any news material contained on this page or on any linked site. The material on this page may include the views or recommendations of third parties, which do not necessarily reflect the views of the program nor it's supporters, or indicate commitment to a particular course of action

 

 

 

 

 

Rehabilitating seagrass in Gulf of Mannar

22 November 2017, Times of India (India)

Concerned at the near decimation of seagrass off the state's coast, researchers have begun a vital rehabilitation programme. They planted saplings in a 200sqm area off Thanjavur and Pudukottai districts, part of the Gulf of Mannar Biosphere Reserve, between March and May this year and are thrilled to find that about 75% of the colourful plants "are now growing well".
Seagrass communities, vital for the survival of the marine ecosystem, including coral reefs, once covered more than 60,000 hectares in the Gulf of Mannar, but various marine activities almost sounded their death knell and the efforts now being taken seem minuscule given the magnitude of the destruction. The damage has not been limited to Tamil Nadu, with researchers saying as much of 35 % of seagrass beds in the country have been destroyed in the past 35 years. Besides, very little study has been done on the plants.

After taking up the three-month rehabilitation project, for which the state forest department sanctioned Rs 4 lakh for each of the two districts, Organisation for Marine Conservation, Awareness and Research (OMCAR) scientists, who possessed scuba diving skills, began extensive fieldwork and planted the saplings.

OMCAR founder V Balaji told TOI the 400 sprigs of seagrass species Cymodocea serrulata and Syringodium isoetifolium were planted in each square metre field formed by burying PVC frames and tied with jute ropes. "We have been monitoring the growth of the transplanted seagrass (as they have vegetative reproduction) periodically. Last month, the buried PVC frames were taken out of the sea to prevent pollution," he said.

While admitting that some of the frames had been damaged by fishing nets, Balaji, however, appeared optimistic that the rehabilitation project would flourish and help convert dead seagrass sites into healthy, thriving beds in the near future.

On the seagrass habitat, Balaji said the most extensive beds occurred on soft substrates such as sand and mud. Seagrass meadows were found in coastal waters of both tropical and temperate regions, but were more abundant in tropical seas in comparison to temperate zones, he said.

The project, Balaji said, was part of the conservation action plan drawn up by the forest department under the TN Biodiversity and Greening Project to protect the dugongs, medium-sized marine mammals largely dependent on seagrass communities for subsistence.

Seagrass, former Zoological Survey of India director K Venkataraman said, had high productivity and provide great ecological and economic services. The ecosystem engendered by seagrass communities is conspicuous and often a dominant habitat in shallow coastal waters. Seagrass meadows are primary producers that contribute large quantities of fixed carbon to the entire coastal ecosystem, he said.

But indiscriminate fishing activities, including operation of trawlers, have been wreaking havoc on their already threatened habitat. In the Palk Bay, vast swathes of seagrass beds have been practically ripped out by trawlers and push nets used by country boats. Seagrass generally grow in an area around 8 km off the shoreline, an active fishing area in the Palk Bay, he added.

More information: Click Here



 

Enormous Extinct Sea Cow Fossil Found on Russian Island

21 November 2017, National Geographic (Japan)

This historic drawing shows a Steller's sea cow in life. COURTESY OF BIODIVERSITY HERITAGE LIBRARY (CC BY), CREATIVE COMMONS

When Maria Shitova saw what looked like white poles jutting out of the sand at a beach in Russia, she thought they were part of a manmade fence. But instead of digging up city planning, her research team exhumed the nearly complete skeleton of a gargantuan sea cow hours later.

The team had to dig less than three feet into the earth on the remote Commander Islands in Russia's Komandorsky Nature Reserve before they found the 17-foot-long remains of the extinct creature. The 10-ton specimen lacks a skull and several bones, but it has 45 vertebrae, 27 ribs, and a left scapula. The well-preserved skeleton will be displayed at the visitor center, nature reserve officials say.

"This is the only sea cow that we've ever found that's intact in situ," says Lorelei Crerar, a George Mason University professor who published a paper on sea cows in 2014. "All we've got is just this one record of this animal and that's it."

In 1987, an almost 10-foot-long specimen was discovered on Bering Island, but it has since been disassembled. Today, The Guardian reports that the Finnish Museum of Natural History has one of the most complete sea cow skeletons in its possession.

Crerar is hopeful the skeleton's head is in the area somewhere, and might be unearthed by further excavation. When Georg Steller, the German explorer who discovered the creatures in 1941, returned from the Great Northern Expedition, he had to leave a sea cow carcass behind. Crerar says this skeleton could be the abandoned animal.

Closely related to other blubbery mammals like modern dugongs and manatees, twenty-foot Steller's sea cows used to swim the waters between Russian and Alaska beginning up to 11,700 years ago. Steller said they breathed air, never submerged, and may have walked on land. Instead of teeth, the fork-tailed creatures munched on sea grass and kelp with an upper lip of white bristles and two keratin mouth plates. They were monogamous, social, and mourned their dead.

"When a female was caught the male, after trying with all his strength, but in vain, to free his captured mate, would follow her quite to the shore, even though we struck him many blows," described an explorer hunting sea cows in 1751. "When we came the next day, early in the morning, to cut up the flesh and take it home, we found the male still waiting near his mate."

At one point, estimates say there were 2,000 sea cows swimming in the Arctic sea. But the animals went extinct in 1768, 27 years after they were discovered. In addition to studying the species, Steller and his crew hunted the animals, likely killing 10 to 20 of them for their meat, Crerar says. Apparently, the gentle giants' 4-inch-thick layer of blubber tasted like almond oil and could feed 33 people for a month.

"Hopefully, there'll be some more information released," Crerar says. "This is a family of animals that was enormous at one point and has shrunk down."

More information: Click Here


 

 

Removal of rotting seagrass in Swan River a last resort, despite bad smell

21 November 2017, Community Newspaper Group (Australia)

A BAD odour caused by rotting seagrass in the Swan River will only be dealt with as a last resort, the Department of Biodiversity, Conservation and Attractions (DBCA) says.

The Department said seagrass and macroalgae often accumulates on shorelines at this time of year, emitting a bad smell as part of the natural breakdown process.

DBCA rivers and estuaries director Mark Cugley said submerged vegetation provided habitat for fish and sea horses and was a food source for black swans.

“Macroalgae and seagrass in the Swan River can grow rapidly at this time of year due to increases in temperature, available light and nutrients,” he said.

“Then, as it dies off, prevailing winds and tides can cause it to accumulate as wrack on some foreshores of the Swan Canning Riverpark.”

Mr Cugley said that while the smell was unpleasant, water movement often disperses the material naturally.

He said the removal of wrack was only carried out as a last resort.

“Where it is practical to remove wrack, it needs to be dry before being taken offsite for disposal and may be stockpiled to dry for several days if required,” he said.

“This decision is made in consultation with local governments, which have a shared responsibility for the foreshore.”

Residents surrounding North Lake experienced their own bad smell in August, with rain helping our dams but doing little for the nose.

People took to social media seeking answers to the cause of the strong smell of faeces affecting people in Kardinya, Winthrop, Melville and even Mt Pleasant.

A DBCA spokeswoman put the bad smell down to the effects of heavy rain at North Lake.

“The area has been investigated and officers have determined that the likely cause of the odour is rotting plant material on the banks of the wetland,” she said.

“The recent above average rainfall has increased the water levels in the wetlands and this has impacted on the fringing vegetation by submerging the grasses and plants, with the plant material beginning to break down and rot over time.

“(This has produced) the associated odour.”The spokeswoman said the odour was more noticeable when large numbers of plants were impacted.

“It is a natural occurrence and the odour should dissipate over the coming days,” she said.

For more information about seagrass and seaweed accumulation, contact the DBCA on 9278 0900.

More information:Click Here


 

 

Fishing 'best argument for seagrass conservation'

17 November 2017, BBC News (UK)

The study details the many different types of gear used to fish among the plants. Photo Credit: Richard Unsworth

The importance of seagrasses is further emphasised in a new report that looks at how they underpin fishing worldwide.

These flowering plants, which grow in near-shore waters, are under intense pressure - some estimates suggest global losses are running at 7% a year.
The grasses provide shelter and food for many sea creatures and that makes them a natural draw to fishers.

But Richard Unsworth and colleagues say this valuable resource will need better management if it is to be sustained.

"Our study is really the first to show just how important seagrass meadows are to fishing," explained the researcher from Swansea University in the UK.
"Wherever you get seagrasses, you get fishing, basically," he told BBC News.

Seagrass meadows are found around every continent except Antarctica.

The plants cycle nutrients, stabilise sediments, and - as photosynthesisers - act as a "sink" for carbon dioxide.

They also provide nursery habitat for juvenile fish, which hide from predators among the stems.

However, the scale of the importance of the meadows to fisheries has been more supposition than fact because of a paucity of data on how they are actually used, according to Dr Unsworth.

His team set about correcting this by interviewing experts - including other scientists and fisheries managers - on what they were observing around the world.

The team also took in case studies covering all regions from the Philippines to Zanzibar, Indonesia, the Turks and Caicos Islands and locations in the Mediterranean.

The picture that emerges is much the same everywhere.

Fishers actively target seagrasses because they recognise the habitats' great productivity.

This is true from small-scale recreational activity all the way through to large-scale commercial practice.

The study details the types of tools and equipment used - from spears to nets - and the variety of species taken, from invertebrates such as crabs, shrimp and clams, to popular finfish such as mullet, herring and snapper.

One critical point to emphasise from the assessment is that many hundreds of millions of people worldwide depend on the catch from seagrass meadows for their daily protein intake.

This makes their conservation and proper management all the more important, says the team.

There is a claim that a meadow area equivalent to two football pitches is disappearing every hour.

Such statements are very hard to verify, but there is no doubt that seagrasses are being diminished by poor water quality in coastal areas as a result of agricultural and urban run-off, among several threats that also include insensitive fishing practices.

Team member Lina Nordlund, from Stockholm University, said: "The ecological value of seagrass meadows is irrefutable, yet their loss continues at an accelerating rate.

"Now there is growing evidence globally that many fisheries associated to seagrass are unrecorded, unreported and unmanaged, leading to a tragedy of the seagrass commons."

Leanne Cullen-Unsworth, from Cardiff University, added: "Arguments in support of seagrass have in the past too often focused on the fluffy - such as the conservation of seahorses.

"I don't want to dismiss seahorses' importance, but the reality is that seagrasses have much higher value in supporting fisheries. And I've come across numerous occasions where fishermen have been against conservation of seagrasses because they can't moor their boats in these locations, when it's those seagrasses that support their activity in the first place.

"What we need to do is increase the level of understanding and appreciation of these habitats."

The team's study - Global significance of seagrass fishery activity - is published in the journal Fish and Fisheries. http://onlinelibrary.wiley.com/doi/10.1111/faf.12259/full

More information:Click Here



 

Rare dolphins and dugongs die after being caught in fishing nets, Barrier Reef authority says

19 November 2017, ABC Online (Australia)

Four dugongs have been found dead near Townsville since September. Two snubfins drown after they were captured in a commercial fishing net in October, GBRMPA said. Photo Credit: Isabel Beasley, JCU

Dugongs and snubfin dolphins have died after being caught in commercial fishing nets in northern Queensland waters, authorities have confirmed.

The Great Barrier Reef Marine Park Authority (GBRMPA) said two snubfin dolphins drowned after being caught in a commercial fishing net operation in October.

"The fisher who caught the dolphins followed all required fishing rules and protocols, including attendance of the net and reporting of the incident," a GBRMPA spokesperson said.

In September and October, four dugongs were found dead in Bowling Green Bay near Townsville, with at least one killed by a commercial fishing net.

GBRMPA said a second dead dugong was found floating in close proximity to a commercial netting operation, while the other two carcasses in the area were too decomposed to determine a cause of death.

The authority only released the information in response to a media inquiry and has refused to reveal where the snubfin dolphins died, due to privacy concerns.

It also said it could not release photographs of the dead dolphins for privacy reasons.

The snubfin dolphins were recovered by marine park officers and taken to a university for research and examination.

"Some of these unfortunate marine mammal deaths relating to net fishing reinforce the importance of mitigating risks and ensuring ecologically sustainable fishery management arrangements are in place adjacent to and throughout the Great Barrier Reef Marine Park," the spokesperson said.

'Barrier Reef needs more net-free zones'

The gillnet deaths have outraged conservationists.

Gillnets are long rectangular nets which are set horizontally along the ocean floor.

WWF Australia head of oceans Richard Leck said more had to be done to prevent such tragic outcomes.

"This is a really tragic incident to hear about. These snubfin dolphins are a rare Australian species they are only found in Australian waters and they're a vulnerable species," he said.

Mr Leck said many gillnet deaths were not reported.

He said WWF Australia was calling for the establishment of an 85,000-square-kilometre net-free zone in north Queensland.

"We're calling for the major parties to commit to more net-free zones in the Great Barrier Reef Marine Park, starting with a large net free zone in the north of Queensland."

Mr Leck also encouraged GBRMPA to be more transparent and to keep people updated on when marine mammal deaths occurred.

"We need this information to be in the public realm to inform people what's happening and to get those best solutions to protect these very vulnerable and incredibly charismatic species into the future."

GBRMPA said there were no further investigations into the deaths as fishers followed all reporting protocols.

It also said the deaths were reported with the Department of Environment and Heritage Protection and made public in annual reports.

More information:Click Here


 

 

Data modelling is key to managing fisheries sustainably

17 November 2017, Phys.Org (Australia)

Have you ever questioned the environmental or economic sustainability of the flathead you order from your local fish and chips shop? Do you know where it's from?

Not all fish are caught in an ecologically sustainable way, but scientists are working with fisheries managers to address this.

"To sustainably manage a fishery we need to know its births, deaths, immigration, migration and growth rates", says Dr John Morrongiello, a fish ecologist at the University of Melbourne's School of BioSciences.

"We also need to know where a fish lives, what it eats and how all these factors are affected by changes in the environment."

Dr Morrongiello's team uses complex data modelling to understand the factors impacting fish stocks.

"This helps us understand how the process of fishing itself affects the fish through changing traits like growth rates."

Dr Morrongiello and his colleagues Dr John Ford, Dr Rob Day and PhD student Joshua Barrow have been working in Corner Inlet in southern Victoria to understand how environmental conditions have affected the growth of the commercially valuable Rock Flathead.

Their research was published in the journal Marine Ecology Progress Series.

What rock flathead growth reveals about sustainably managing fisheries

The team measured the changes in growth patterns of 526 Rock Flathead fish collected over 32 years, and analysed these against environmental factors like temperature and river flow. They ran the data through several climate change scenarios to see likely growth rates in 2030 and 2070.

After accounting for factors like age (old fish grow slower than young fish) and sex (females grow faster than males), the researchers showed Rock Flathead grow faster when there are higher river flows and at higher water temperatures.

Growth was measured using bones in the fish's head called otoliths that play a role in hearing and balance. Lead author Mr Barrow says these otoliths have the fish equivalent of tree rings, and can indicate the age of the Rock Flathead.

"If you take a section of the otolith, it has rings like a tree trunk and so you can see how fast the fish grows, how old it is and which particular years line up with those environmental conditions."

Mr Barrow says the high river flows correlate with more seagrass growth, an important habitat for flathead, which are an ambush predator.

Higher temperatures mean more seagrass meadows, and directly help the cold-blooded flathead fish by allowing them to be more active and hunt for food.

The climate change models showed that the fish are likely to grow faster as the climate warms.

"River flows are predicted to decrease, but these will likely be offset by rapid increases in temperature," says Mr Barrow.

This study compliments a larger body of research led by Dr Ford, which examines the changing coastal habitats of Corner Inlet, in Victoria's Gippsland, in relation to variations in the density of seagrass cover over the last 50 years. The researchers have found that decades of intensified weather events, algal blooms and chemical pollutants have contributed to a decline of seagrass in the area.

"By combining this finding with John's larger project investigating what's driving seagrass decline and recovery, we can provide a clear link between the Rock Flathead's habitat and how this actually affects the commercial fishery," says Mr Barrow.

How can data modeling help manage fish stocks?
Australian fisheries are using this kind of data to help ensure the ongoing viability of their industry.

"It's giving us a very clear indication of whether we might be driving those stocks into the negative or whether we are getting the maximum, or the optimum, productivity out of them," says Dr Ford, an independent sustainability accreditor and honorary researcher at the University of Melbourne.

"What sustainability is all about is balancing this desire to continue to feed a growing population in a world which supports the actual ecosystem."

Dr Morrongiello says that to manage both the environmental and economic impacts of fisheries we need a collaborative effort between consumers, scientists and industry.

"We are generating the scientific knowledge and have a supportive industry and government so there is no excuse why we can't get good outcomes," says Dr Morrongiello.

"It's about managing the fine balance between having a sustainable and viable fishery supported by a healthy ecosystem, and over-harvesting a resource or degrading the environment and causing fisheries to collapse.

"Thankfully, we get the balance right more often than not in Australia."

How can we, the consumers, help?
So what can we as consumers do to make educated choices and help promote sustainable fisheries? There are three easy ways to achieve this.

Buy Australian fish that is locally sourced
Australian fisheries operate within strict codes and practises that ensure their sustainability. They rely on research to maintain a healthy ecosystem, as well as a sustainable population.

Diversify your choice
Don't just choose tuna or salmon, as demand for certain types of fish can lead to overfishing and population depletion. Choose from a variety of locally sourced and regionally specific fish to support the local industry and maintain diversity within our oceans. Sustainable and under-appreciated species include sardines, leatherjacket, mackerel, squid/calamari and mullet.

Look for eco-labelled products
The Marine Stewardship Council gives sustainable fish products a blue tick to help consumers make ecologically sound choices.

More information:Click Here



 

Seagrass study key to ecosystem success

10 November 2017, Griffith News (Australia)

Photo Credit: Megan Saunders

Declining seagrass meadows in Moreton Bay will be studied by an international team of researchers to overcome the largest remaining barrier to effective management of the world’s marine resources.

The team, led by researchers from the Australian Rivers Institute at Griffith University and funded by the Australian Research Council, will develop new software tools that will help manage the cumulative impacts that threaten coastal ecosystems.

Ecosystems like seagrass meadows, mangroves and coral reefs are highly threatened but globally important. They provide habitat for fish, support fisheries, capture carbon from the atmosphere and are food for many animals including dugongs.

Lead Dr Chris Brown said decision makers must manage a bewildering array of threats that coastal ecosystems face.

“Many coastal ecosystems are threatened by urbanisation, overfishing, pollution and climate change all at once,” he said.

“Managers are often unsure about how to plan for cumulative impacts. They typically have very limited data on how cumulative impacts interact to degrade ecosystems.

“The tools we aim to develop will help make reliable predictions about cumulative impacts, even where there are little data. ”

Professor Rod Connolly, a chief investigator on the grant, said the project aimed to overcome the largest remaining barrier to effective management of the world’s marine resources.

Seagrass ecosystems in Moreton Bay have been in decline for decades due to multiple pressures brought on by urbanisation of Brisbane and surrounds.

The team will collect new data to test the ability of the software tools to predict the impact of cumulative impacts, including urbanisation and pollution.

The team then aims to scale up the tools developed for Queensland seagrass so they can be used elsewhere.

The team also includes Professor Côté from Simon Fraser University in Canada, an international expert on cumulative impacts. Canadian seagrass meadows face many of the same threats as those in Australia, making it a perfect testing ground for the new tools.

“This is a unique opportunity to provide practical tools, underpinned by strong science, for decision-makers to tackle the most complex issues that affect coasts around the world,” Professor Côté said.

“We hope that the results of this project will reduce the amount of guesswork currently involved in managing threatened coastal habitats”

More information:Click Here



 

Algal blooms return to Florida Bay – Keys News

08 November 2017, KeysNews.com (USA)

Contributed Audubon scientists observe seagrass floating in Florida Bay shortly after Hurricane Irma.

Algal blooms, which kill fish, suffocate seagrass and make life harder for those who rely on the Everglades estuary for their livelihoods, have surfaced again this year.

Bob Johnson, director of the National Park Service’s South Florida Natural Resources Center, says that large areas of Florida Bay are beset by blooms, which is not surprising after Hurricane Irma and more recent weather events churned up the nutrient-rich bay bottom, one of many likely contributors to the problem.

Pete Frezza, a local fishing guide and research manager for Audubon’s Everglades Science Center, says he’s noticed algal blooms in different areas of the bay.

“It’s gotten pretty bad,” Frezza said. “There is very little water in the bay now that doesn’t have some type of bloom. The only place that looks fine is the areas where there are strong Atlantic tides near the Keys.”

Frezza points to dead seagrass as one possible culprit, as it releases nutrients that feed algae when it decays. About 22,000 acres of seagrass meadows died after a drought in 2015, which likely helped feed algal blooms that appeared shortly thereafter.

“We had a massive amount of floating seagrass come into Florida Bay from the Gulf of Mexico during Irma,” Frezza said. “A lot of that grass most likely sunk into the bay, and when that plant matter breaks down, that’s another release of nutrients.”

Another potential source of nutrients is freshwater flow from the Everglades via central Florida, namely Lake Okeechobee. Frezza says that while Florida Bay relies on freshwater flow, much of what comes into the bay now is nutrient-laden and carries pollutants.

“More freshwater flow is something we want, but this water is moving through agricultural areas (and) urbanized areas where there are high concentrations of nutrients,” Frezza said. “We have a lot of water moving into the bay with elevated nitrogen and phosphorus levels, which can spur the growth of these blooms.”

A reservoir to be built south of Lake Okeechobee, which would store and filter water before it flows south, is in the works, and Frezza says the reservoir could be a significant factor in preventing future algal blooms.

“I imagine (the reservoir) would have helped the situation, absolutely,” Frezza said. “That reservoir will allow for a timely distribution of water, as well. That certainly could help.”

Steve Davis, an Everglades Foundation ecologist, is less sure that runoff is contributing to the algal bloom this year. He points to dead seagrass and an intense rainy season as likely factors in the most recent algae threat.

“It’s not any upland source of pollutants,” Davis said. “It’s not freshwater inflow that’s a bad thing, it’s just that we’ve got all this dead grass out there. Once the (nutrients) are released into the water, algae is much faster growing and more adept at taking up nutrients than seagrass, which has to grow roots and become stable and needs lots of light.”

Drought, which killed off so much seagrass in 2015, is not an issue this year, as rain has reduced salinity levels in Florida Bay significantly, according to Davis. Though the threat of drought killing off seagrass is not currently an issue, past die-offs still potentially haunt the bay when it comes to the formation of algae.

Another factor is that while many believe that Irma actually flushed out the bay, it also blew seagrass and other nutrient-rich plant material into it, which has created conditions which can allow algae to flourish.

“We saw this type of phenomenon with Wilma and in previous storms. Lots of grass and mangrove leaves get moved around and deposited,” Davis said. “We can’t discount the contribution of that (seagrass die-off) to what we’re seeing today in terms of having a compromised Florida Bay.”

National Park Service testing of chlorophyll-A levels, which indicate the presence of algae and cyanobacteria, are sky-high in some parts of Florida Bay, according to Johnson.

“Our last measurement post-Irma (indicates) that we have very high levels of chlorophyll-A in the water column,” Johnson said. “The (Florida Department of Environmental Protection) standard for central Florida Bay is about 2.2 micrograms per liter. We’re up to about 30 to 40 in that part of the bay.”

Other areas of the bay measure at as much as 200 micrograms per liter, according to Johnson, meaning that it’s all but certain that a major algal bloom event is not only happening now, but is likely to persist for some time.

“Some of this is expected, but the problem is that it’s happening right after the prior seagrass die-off and algal bloom. That’s why it’s likely going to persist longer than we’d normally see,” Johnson said, adding that the current bloom could last “for six months or so.”

Davis says it’s tough to pin down one factor that may be causing the current bloom among sediment disruption, the release of nutrients from dead seagrass and other foliage, and other possible contributors.

“If the seagrass beds were healthy and intact, it may not have been so bad,” Davis said. “I can’t say that without a controlled experiment, and when you’re working with Mother Nature it’s hard to have a controlled experiment of this scale.”

Paul Tejera, a local fishing guide who recently ran a backcountry tournament to benefit guides, told the Free Press that the fishing in that tournament and in his experience so far this year has been “very good,” indicating that the nascent bloom may not yet be affecting fish and other wildlife populations.

That’s welcome news for the many industries that rely on a healthy fish stock to survive, though if an algal bloom is indeed taking hold in Florida Bay, those conditions could rapidly change.

As scientists and others continue to monitor the situation, Frezza says those who haven’t ventured out into Florida Bay much past the coastline may not have noticed much change yet, though he says some in Key Largo are already complaining about the quality of the water.

“It’s all in their backyards in Key Largo, but it’s not as bad there as it is in the central bay,” Frezza said. “I don’t think people realize how much worse it looks.”

For him and everyone else who is concerned with the health of Florida Bay, another widespread bloom would hardly be a surprise, as Frezza says they happen now with disturbing regularity.

“It’s large in extent. This is not unprecedented, though,” Frezza said. “To have a (bloom) this big is a little odd, but algal blooms are common now.”

More information:Click Here


 

 

For seagrass, biodiversity is both a goal and a means for restoration

08 November 2017, Phys.Org (USA)

Seagrass beds are important but vulnerable coastal ecosystems in the Coral Triangle. New research shows that planting multiple species of seagrass is more effective for restoring seagrass beds than single-species planting. From left, Jordan Hollarsmith of Hasanuddin University, and Susan Williams and Katie DuBois of UC Davis look at seabed plots in Indonesia. Photo Credit: Christine Sur/UC Davis

Coral reefs, seagrass meadows and mangrove forests work together to make the Coral Triangle of Indonesia a hotspot for marine biodiversity. The system supports valuable fisheries and endangered species and helps protect shorelines. But it is in global decline due to threats from coastal development, destructive fishing practices and climate change.

A UC Davis study published recently in the journal Proceedings of the National Academy of Sciences found that in the case of seagrasses, biodiversity is not only a goal, but also a means for restoration of this important ecosystem.

The Coral Triangle is home to about 15 species of seagrasses, more than almost anywhere else on Earth. Previous seagrass restoration efforts have primarily focused on a single species.
For this study, the scientists transplanted six common seagrass species at four species-richness levels: monocultures, two, four, and five species. They analyzed how well the initial transplants survived and their rate of expansion or contraction for more than a year. The results showed that planting mixtures of diverse seagrass species improved their overall survival and growth.

"Seagrass beds are important habitats for fisheries species, for protecting shorelines from storm damage, and they provide livelihoods for many millions of humans around the world," said Susan Williams, a professor in the UC Davis Department of Evolution and Ecology and the UC Davis Bodega Marine Laboratory. "Seagrass habitat is being lost at a rate of a football field's area every half-hour, which threatens these important functions. We demonstrated we could improve seagrass restoration success by planting a mix of species, and not just a single species, which has been the common restoration practice in warm regions such as Florida, Texas, and also in Indonesia, where we performed the experiment."

More information:Click Here


 

 

It's Manatee Awareness Month: 5 Facts About These Marine Mammals

07 November 2017, Parade (USA)

Seagrass beds are important but vulnerable coastal ecosystems in the Coral Triangle. New research shows that planting multiple species of seagrass is more effective for restoring seagrass beds than single-species planting. From left, Jordan Hollarsmith of Hasanuddin University, and Susan Williams and Katie DuBois of UC Davis look at seabed plots in Indonesia. Photo Credit: Christine Sur/UC Davis

Often referred to as sea cows, manatees are gentle, bulbous goofballs with a penchant for sleeping and eating—but despite their laid-back lifestyle and mellow demeanor, frequent collisions with watercraft (and another human interferences) put these marine mammals at risk. While the U.S. Fish and Wildlife Service recently downgraded manatees from endangered to threatened status, National Manatee Month is a good time to remind ourselves what makes sea cows so cool.

Manatees like to hang out in shallow coastal areas and rivers, munching on vegetation like algae and sea grass. They eat up to nine percent of their body weight in plants every day—and with weights up to 1,200 pounds, they can spend nearly half the day chowing down.

Some types of manatees (West Indian and West African) are able to live between fresh and salt water areas thanks to a regulation system in their kidneys that keeps salt concentrations in check.

While manatees are called sea cows, their closest relative is actually the elephant. Fossil records indicate that manatees and elephants evolved from the same land over 50 million years ago.

Christopher Columbus thought that manatees were mermaids, writing the sea maidens were “not half as beautiful as they are painted.”

Sea cows can hold their breath for up to 20 minutes, but they opt to go to the surface every three to five minutes. Also, when they take a breath, they replace 90 percent of the air in their lungs—humans only replace about 10 percent.

https://parade.com/616885/ccopelan/its-manatee-awareness-month-5-facts-about-these-marine-mammals/

More information:Click Here


 

 

A New Way to Look at Eelgrass

03 November 2017, East End Beacon (USA)

Eelgrass being studied by Dr. Peterson’s Marine Community Ecology Lab at SOMaS. | Photo Credit: SOMaS photo

It’s easy for East Enders to think of the eelgrass that has provided habitat, most famously, to the Peconic Bay scallop, as a part of our lost heritage. But seagrasses, essentially rooted grasses that thrive when fully submerged, have become threatened throughout the world.

Right here on Long Island, we’re doing some groundbreaking research that could have positive implications for seagrasses around the world.

Dr. Bradley Peterson, a marine ecologist with Stony Brook University’s School of Marine and Atmospheric Sciences’ labs in Southampton, has been following the fate of Long Island’s eelgrass since he joined the faculty at the campus, formerly part of Long Island University, in 2003. He gave a presentation on his research at the college Oct. 20.

“Submerged aquatic vegetation is among the most productive of marine environments,” he told a crowd of students and interested community members. “It requires a lot of light and grows in shallow water, which is one of the reasons it is in such peril.”

You know all those algae blooms you’ve been hearing about on the news? The ones that are caused by excessive nutrients entering our bays? Well, sea grasses are one of the biggest victims of algae blooms.

“The first thing that seems to disappear with overnourishment is light,” said Dr. Peterson.

“Seagrasses require 10 to 30 percent surface light. After that, things start growing in the water, and there’s no light on the bottom.”

Dr. Peterson said the world has lost one-third of its seagrass since 1880. We’re currently losing a football field every 30 minutes, and the rate of decline in seagrass since 1990 has sped up to 7 percent per year.

On Long Island, he said, about 23 percent of the sea grass in our estuaries disappeared between 1967 and 1977, due to increasing nutrients, and another 40 percent disappeared during the brown tide explosion between 1985 and 1988.

There’s been a lot of research and restoration work attempts in the Peconic Bays and South Shore estuaries since the brown tide explosion, but Dr. Peterson said some of the early research has proven wrong.

Initially, seagrass experts who were brought in said Long Island’s seagrasses were suffering because of “poor connectivity and inbreeding.”

Zostera marina, a.k.a. eelgrass, can reproduced through clones, sending out shoots from existing plants, but it can also grow from seeds. Initially, researchers believed the genetic similarity of these clones were the reason eelgrass couldn’t adapt to algae blooms.

“We found that to be absolutely false,” said Dr. Peterson. “If you went more than eight steps away, you never found another clone. That tells you our population is driven by seeds.”

Much of the effort to replant eelgrass on Long Island has centered around replanting shoots of eelgrass in locations where they had historically been known to grow, often weaving the seedlings into a round burlap mat before placing it on the sea floor.

Dr. Peterson said there has been little success after years of attempting to replant eelgrass beds using this method, at a cost of nearly $1 million per acre. And areas that seagrass has liked in the past have changed, and may no longer be as conducive to the spread of sea grasses as they were before.

But collecting eelgrass seeds and dispersing them directly has proved a promising and cost-effective method, he said, when coupled with doing work to help improve the ecological health of our estuaries, by reducing nutrients into the bays and by seeding them with shellfish that can filter algae from the water. It’s about understanding the connectivity of an ecological system, not just about keeping your eye on seagrass.

“We can collect six million seeds with two weeks’ work,” and broadcast them onto sandy bottom lands, he said. “If we can actually change the system, the plant itself has a vast ability, from seeds, to change the space.”

He pointed out slides of an area of Shinnecock Bay that had been planted with seeds. The area had initially been covered only 3 percent by seagrass. When left alone for six years, however, that area jumped to 43 percent coverage.

“That’s a natural seed set that grew and coalesced in Shinnecock Bay,” he said. “We made no improvement. That’s just natural progression.”

“Everybody wants to do something. They see a problem and they want to do something,” he said. “But where it was is not the same as where it was before. A lot of people spend a lot of money putting it back where it was. We have only so much time and money. I’m not telling you seeds will work everywhere, but we have seen some success.”

This success is important for many reasons, not the least of which is helping to provide crucial habitat to restore the Peconic Bay scallop.

“Eelgrass is more productive than a tropical rainforest,” said Dr. Peterson. “A lot of things live in them and hide in them, and they play the role of a nursery for shellfish and fin fish.”

He added that seagrasses provide three times the habitat of coral reefs.

Globally, seagrasses also play a big role in locking up atmospheric carbon, making them a fighter in the race against climate change. During that process, they also increase the pH of their surroundings, fighting off the linked threat of ocean acidification.

“Seagrasses, tidal marshes and mangroves only exist on .2 percent of the marine footprint, yet they’re responsible for 50 percent of its carbon sequestration,” said Dr. Peterson. “We can use restoration of habitats to drive down carbon.”

The fall SOMaS lecture series continues on Friday, Nov. 3 at 7:30 p.m., with a talk by Dr. Joe Warren on “Dining with the Leviathans of the Oceans. On Dec. 8 at 7:30 p.m., Christopher Paparo will give a talk on “Exploring Long Island’s Underwater World.” Both lectures will be held in the Duke Lecture Hall in Chancellor’s Hall.

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First-ever sea grass nursery aims to restore Indian River Lagoon

02 November 2017, WESH Orlando (USA)

Watchdogs of the sensitive Indian River Lagoon are celebrating a breakthrough that might help bring back the ailing waterway.

WESH 2's Dan Billow visited the first-ever seagrass nursery.

It's a place where large-scale restoration can take root.

Even after getting thrashed by a hurricane, it's coming back. In an underwater nursery just off a runway at the Merritt Island Airport, seagrass is taking root, planted not by Mother Nature but by people.

"This is the first time we know of that nursery-grown seagrass has been transplanted and tried in the Indian River Lagoon," said Keith Winsten, of the Brevard Zoo.

Seagrass is the basis of life, and tens of thousands of acres of it have been lost.

Sewage dumping, muck buildup and toxic runoff have combined to kill off the grass, but a public-private partnership has found the recipe to regrow it.

"Without seagrass, you're not going to have shrimp. You're not going to have crabs. You're not going to have a place for juvenile fish to hide," said Laurilee Thompson, a private donor.

Thompson is the owner of the famous Dixie Crossroads Restaurant. She is one of several private donors who made the project possible, thereby providing a potential lifeline for the lagoon.

"It's dear to my heart. I've watched it for 65 years. I'd like to see the waters crystal clear again, and productive," Thompson said.

"The process that they have revolutionized I believe will catch on," said Michael Powell, of the Titusville-Cocoa Airport Authority.

"I think the process has real potential. We just have to see how fast it grows in and what the costs are down the road," Winsten said.

The nursery takes up 1 acre. The next step is to find a way to regrow thousands more.

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Study identifies bottlenecks in early seagrass growth

01 November 2017, Phys.Org (Australia)

VIMS professor Robert JJ Orth examines a bed of Posidonia australis seagrass within Cockburn Sound, Western Australia. This species has suffered substantial losses here and elsewhere due to nutrient pollution and industrial development of the coast. Photo Credit: S. Manley/VIMS.

Seagrass meadows, key nursery and feeding grounds for many kinds of marine life, are being lost worldwide to nutrient pollution, warming waters, and other ills. A new study by an international research team reveals bottlenecks in the growth of seagrass from seed to seedling, knowledge useful for improving seed-based restoration efforts.

The study authors are John Statton, Leonardo Montoya, and Gary Kendrick of the University of Western Australia, Robert Orth of William & Mary's Virginia Institute of Marine Science, and Kingsley Dixon of Curtin University in Perth. Their work appears in today's issue of Scientific Reports, an open-access journal from the publishers of Nature.

"The science behind seed-based restoration is very underdeveloped for most seagrass species and lags severely behind that for land plants," says Statton. One notable exception is the success of using seeds to restore eelgrass to Virginia's seaside bays; work pioneered by Orth during years of trial and error testing both seeds and transplanted shoots.

In the current study, the researchers sought to understand the journey from seed to seedling for the Australian seagrass Posidonia australis or ribbon-weed. This slow-growing species has experienced serious declines over much of its range, earning it a "near threatened" status on the IUCN Red List.

The team conducted their study by painstakingly monitoring the fate of more than 21,000 P. australis seeds hand-planted within experimental plots in Western Australia's Cockburn Sound. They sited the plots to test varying degrees of exposure to waves, seed grazers such as crabs, and "bioturbators," animals that inadvertently bury seeds during burrowing or other activities—often too deep for subsequent development.

Unlike most other studies of seagrass growth, which have simply looked at the overall proportion of seeds that reach maturity as adult plants, Statton's team carefully followed the progress of their seeds at each step from germination to seed-dependent, seed-independent, and established seedlings.

"By identifying the exact early life-stage transitions that limit seagrass recruitment, we think we can improve our ability to target the processes most responsive to management," says Statton. "These bottlenecks may be unique for each seagrass species and even a particular location," adds Orth.

The team's results showed clear differences in seed success among the various life-stages. In the shallower, more-sheltered sites, few if any seeds survived grazing and bioturbation to complete the initial life-stage transition—the first month of growth when a germinated seedling still relies on its seed for energy. Seeds deployed in deeper sites survived for another four to six months, before almost all the now-independent seedlings were uprooted by waves from winter storms. As a result of these challenges, overall seed survival was vanishingly low—with fewer than 1 in 1,000 seeds reaching the juvenile stage—a probability of just 0.1 percent.

The researchers then used models to estimate the seeding density needed to overcome these severe bottlenecks, calculating success at seeding densities 2- to 40-times higher than their field studies. Here their results suggest the more seeds the better, although they note additional fieldwork is needed to test for diminishing returns in growth due to overcrowding of seeds and competition for limited resources.

Although the bottlenecks to growth observed in the Australian study might seem overwhelming, Orth notes they are actually in line with findings from other studies of both seagrasses and land plants. "In our restoration efforts in the seaside bays of Virginia's Eastern Shore," he says, "the probability of seed survival is only about one to five percent."

Despite this, repeated seeding by VIMS researchers has led to restoration success. "In 1997 there was just a small patch of eelgrass in South Bay," says Orth. "Now, 71 million seeds later, there are more than 7,000 acres, and the grass is spreading naturally."

A similar approach might thus work in Australia and other areas worldwide where seagrasses have succumbed to cloudy waters and coastal development. "Our results indicate that seeding may be an appropriate strategy for restoring P. australis," says Statton. "But," he adds, "we would need to do so annually for a decade or more to escape both the summer bottlenecks associated with bioturbators and grazers, and the winter bottlenecks associated with storm waves."

"This approach would allow us to benefit from windows of opportunity," he explains, "benign years when winter storms were relatively weak or came from directions where landmasses blocked most waves. These conditions would allow seagrass seeds to take root and survive."

The team's field and modeling results suggest a number of other strategies to maximize restoration success. For wave-sheltered sites, these include relocating or excluding the crabs and other invertebrates that currently dislodge or eat most seeds and incipient seedlings. "In wave-exposed locations," says Statton, "we might introduce mixtures of seeds and seedlings from species adapted for turbulent conditions, thus providing some seafloor stability for the survival of P. australis."

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