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Water Hyacinth Thrives in Drought Stricken Delta

Forty-nine-year-old Roger Kelly is a Stockton lifer, born and raised in the Sacramento-San Joaquin Delta. River culture is in his blood, and whether alone or taking the helm as a boat club commodore, he is a fixture on the water.

But for Kelly, a growing menace this year has pushed him off the water and left his boat in the weeds. The scourge is an invasive plant known commonly as the water hyacinth. Having no natural controls, it has proliferated, choking boat navigation and marinas in much of the Delta’s 1,000 miles of waterways.

The plant is hardly new, and usually cold winter temperatures and heavy rain are the answer to seasonally killing it off in the winter months. But this year an unwieldy combination of drought conditions and nutrient-loaded water has created a perfect storm for its growth. State and local agencies have dumped millions into control efforts, but the species has grown so dense in areas that it has become a threat not only to boat safety but also to the ecological balance of the Delta.

In November, the California Division of Boating and Waterways moved to address the problem with a program of spraying herbicide and in December through mechanical harvesting, but has had limited results. The state senator who represents the Stockton area recently met with a number of local stakeholder organizations, state agencies, the U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS) and NASA (which creates aerial survey maps of the water hyacinth) to discuss solutions to the weed’s infestation.

“Every year I can remember seeing a little bit of hyacinth, but it seems like in the last four or five years it’s gotten much worse,” said Kelly, whose home sits on the bank of the Calaveras River. “This year by far is the worst that anybody has seen it.”

San Joaquin River at Connections Slough. Photo: Roger Kelly.
San Joaquin River at Connections Slough. (Photo by Roger Kelly)

Water hyacinth (Eichhornia crassipes) floats on top of fresh water and is characterized by thick, shiny green leaves and lavender flowers. Native to the Amazon basin, it was originally introduced from South America to the U.S. at the 1884 World’s Fair in New Orleans. From there it invaded the Mississippi River, flourished in Floridian waters and eventually made its way into the warm flows of California’s Sacramento-San Joaquin Delta about a century ago.

The sub-tropical species is extremely prolific and can double in size in fewer than two weeks of hot weather, creating a dense mat of floating vegetation of up to six feet thick. The plant reproduces both sexually and asexually, cloning itself and also dropping seeds into the soil that can linger for years.

Ecologically, blankets of hyacinth can limit the amount of sunlight that reaches other plants below the surface, interrupting photosynthesis and killing plants and microorganisms important to wildlife. Dead fish have also been seen on the hyacinth, victims of suffocation after jumping on top of the green thickets and being unable to return to the water.

The ecological imbalance caused by the plant has also led to new pest control problems. A new federally funded Area-Wide Pest Management Project grant headed by the USDA-ARS, which includes cooperation from the San Joaquin and Contra Costa Mosquito Vector Control Districts, is examining how the hyacinth acts as a breeding ground for mosquitos.

“They’ve seen an association between dense populations of water hyacinth and mosquitos nearby,” said Patrick Moran, research entomologist with the USDA’s Western Regional Research Center in Albany, CA. “One of the things we are studying is whether or not the water hyacinth makes it difficult for predators to get to the mosquito larvae.”

Like many invasive plant species, Eichhornia crassipes is notably attractive. Photo: confierconifer/Flickr
Like many invasive plant species, Eichhornia crassipes is notably attractive. Photo: confierconifer/Flickr

This year was particularly bad for water hyacinth control because of the severe drought and more nutrient-rich water. The high temperatures and low water flows accelerated the plant’s growth, and more stagnant water has led to a higher concentration of farming fertilizers and treated municipal sewage that isn’t being flushed out of the system, according to the Delta Stewardship Council’s Rainer Hoenicke, deputy executive director of the organization’s science program. The Sacramento wastewater treatment plant, which serves 1.4 million customers, has become a contributing factor to the water hyacinths growth rates.

“It’s the cascading effects of a drought that results in higher temperatures and less nutrient dilution and they are going hog wild,” Hoenicke said.

Over the decades, authorities have conjured up a host of far-fetched and ineffective control measures ranging from dousing the plant with oil to introducing African hippopotami to eat it. The congressional hippo bill failed to pass in the early 1900s and the animals never made their way to America, but the idea of importing a non-native species to combat another one did.

Forty years ago, the U.S. Army Corps of Engineers used helicopters to drop two types of water hyacinth weevils — small crop pests known as Neochetina eichhorniae and Neochetina bruchi — to remote areas of Louisiana to destroy the plant by eating it, and the N. bruchi weevil was later imported to Northern California for the same purpose. The program ceased in the 1980s, and while the weevil still exists in the Delta today, so do larger concentrations of water hyacinth.

San Joaquin River. Photo: Roger Kelly.
San Joaquin River. Photo: Roger Kelly.

Now a similar project is taking shape at the USDA-ARS’ center in Albany. With respect to the weevil, researchers are looking into the possibility of importing an Argentinian version, according to Moran, an entomology specialist, from regions where the insect thrives in a climate similar to that of the Sacramento-San Joaquin Delta, as opposed to the more tropical version imported in the past.

“The hypothesis that we are pursuing is that there could be the same species but a different collection of the weevil that might be better adapted to the conditions here in the Delta,” Moran said. “We are also planning to release a new insect, the water hyacinth planthopper Megamelus scutellaris, which was previously released at a couple of sites by the [California Department of Food and Agriculture].”

The Division of Boating and Waterways is also part of the multi-agency project and is spearheading the control effort, which has included herbicidal spraying of more than 2,400 acres of water hyacinth in 2014 and mechanical removal of the weed near Stockton. But herbicides are limited in their effectiveness because rain can dilute their potency and year-round spraying could harm migratory fish. During the spray season between March and November there are also restrictions on chemicals that can be used in certain areas.

The control program is an ongoing battle with no end in sight. Seeds from water hyacinth have established themselves in the sediment and will continue to germinate even if all surface plants are removed from the water. These seeds have been reported to survive up to two decades in dried mud, according to Vicky Waters, deputy public information officer at California State Parks, which oversees the Division of Boating and Waterways.

“There is no known eradication method for the water hyacinth in the world,” she said.

The stem of the San Joaquin River as it meanders through the Delta. Photo: Roger Kelly
The stem of the San Joaquin River as it meanders through the Delta. Photo: Roger Kelly

Meanwhile, Mother Nature is most effective at destroying the plant. Cold temperatures mixed with heavy winter rains usually push water hyacinth into the saltwater portions of the Delta, where it dies, but changes in climate this year have not made this possible. This has resulted in economic losses and political turmoil over public safety.

Recreational boating generates about half a billion dollars worth of business in Northern California, said Bill Wells, California Delta Chambers and Visitor’s Bureau executive director, and boating clubs and guide fishing have been particularly hit hard. In late fall, water hyacinth had inundated downtown Stockton and strangled the port to such an extent that it also forced the city to cancel the 35th annual Delta Reflections Lighted Boat Parade, previously scheduled for December 6.

Wells said the situation has created a “national security” risk, especially for fog or nighttime navigation. For boats using radar, dense areas of the weed in the rivers show up as solid landmasses.

“There are a million facets to the problem and it’s very serious,” Wells said.

In times of great fiscal pressure on the state government, budgeting for water hyacinth control has also been an issue. The Division of Boating and Waterways Aquatic Weed Control Program spent more than $7 million last fiscal year and allocated more than $9 million for 2014-2015.

On December 15, State Senator Cathleen Galgiani hosted a town hall meeting with a panel of experts from the Division of Boating and Waterways, California Delta Chambers and Visitor’s Bureau, the Port of Stockton, USDA-ARS and NASA-Ames Research Center to discuss both the water hyacinth and another invasive weed, Egeria densa, which, like a freshwater seaweed, has spread beneath the surface of the water. The tag team combination of these two South American infestations — the water hyacinth on top and Egeria densa below — has created what has been called a “green menace” in the Delta.

On a December afternoon, as Roger Kelly sat inside his home on the bank of the Calaveras River, he could hear the machines removing the plant. He went down to the river to film a vessel slicing and dicing up the green weeds.

“It looks like a lawnmower going through the water,” he said.

To the uneducated observer, it would seem progress was being made, but Kelly sees it differently. “This is ten-fold worse than I’ve ever seen it before.”

Nonetheless, he still sees hope for the waterways he calls home. One bright spot is the heavy rain that recently hit the state. Being a mobile surface plant, new water flows could help push this year’s crop out of the river system. Another hope is for a cold winter this year to kill off most of the tropical menace. But even if this occurs, Kelly knows the plant will return in spring and begin to spread again, just like it does every year. He said the only thing people can do is to report the water hyacinth to the authorities when they see it early in the season. This awareness, he insists, could make a dent in its vast coverage before it grows out of control.

“I think there are ways around this,” he said.

High Temperatures Threaten Sacramento River’s Fall-Run King Salmon

Salmon eggs need river temperatures of 56 degrees or less to survive; at 62 degrees there is a 100 percent mortality rate. So when areas of the Sacramento River hit the low 60s in late August, it made a big splash.

The early fall Chinook (also known as king) spawning run is now taking place between Red Bluff and Redding, but prolonged drought has led to reduced flows from Lake Shasta and high water temperatures down river, a situation that could deal many egg nests a death blow. The dangerously warm water recently prompted the Golden Gate Salmon Association — a Petaluma-based coalition of salmon advocates — to call on federal and state agencies to act.

“In a good year, salmon will spawn in the last 60 miles of the river, but this year we don’t have 60 miles,” said John McManus, executive director of the GGSA. “Right now they are crowding into the upper 8 miles trying desperately to find a spot.”

In a recent open letter addressed to eight federal and state agencies, the GGSA proposed the collection and incubation of eggs from wild fish along with the injection of those eggs into spawning ground gravel when river temperatures begin to cool to favorable levels. The technique has been used successfully in Oregon and Alaska but not California. The decision on whether or not to move forward would be a joint one between California Department of Fish and Wildlife, National Marine Fisheries and the U.S. Fish and Wildlife Service. October’s weather will largely influence on the outcome.

“Nobody thinks it’s going to be a good year for egg survival,” said Robert Clarke, a Regional Fisheries Program supervisor at USFWS. But it’s difficult to predict precisely how many eggs will die, he said.

If the drought continues into the heart of the fall spawning season, Clarke said, it is likely that Coleman National Fish Hatchery, located about 20 miles southeast of Redding and managed by USFWS, would be the location for egg incubation. He said the staff there is currently analyzing its capacity to support egg incubation.

The theory behind the egg injection process is that it offers good hatch rates while only minimally altering natural traits, resulting in stronger fish with a better chance of returning to their natural streams than those raised in a hatchery. Only about 10 percent of salmon eggs survive in nature, but up to 90 percent could hatch if inserted correctly in gravel with a hydraulic egg-planting device, McManus said.

However, according to Jim Smith from USFWS’s Red Bluff office, if state and federal agencies do decide to take action, they are more likely to release into the river hatchery salmon fry — very young salmon minnows that live in fresh water —as opposed to injecting the eggs into the gravel. This process is easier than capturing wild and transporting them to the hatchery, Smith said, but this plan poses challenges as well. He said that between 85 to 90 percent of the salmon that return to the Coleman National Fish Hatchery have never spawned in the wild and instead swim back to the hatchery as adults to lay eggs in captivity.

“Because you are artificially selecting, your natural population loses its fitness,” Smith said. “It doesn’t produce as well as natural fish.”

With Sacramento River water running low, state and federal agencies stepped in earlier this year to truck juvenile salmon from hatcheries to San Pablo Bay. (Photo by Steve Martarano, USFWS)
With Sacramento River water running low, state and federal agencies stepped in earlier this year to truck juvenile salmon from hatcheries to San Pablo Bay. (Photo by Steve Martarano, USFWS)

The warm water that poses a threat to this year’s eggs also carries with it consequences that could reverberate for a long time to come.

“That can cascade down through the years,” Clarke said. “Salmon return in cycles, so if you have super low abundance one year, the loss of that year’s class carries through for a while.”

Even though a potential exists this year for a high mortality rate, high juvenile survival rates coupled with good ocean survivability in the first two years are still possible. “Those things might mitigate the low survivability of the eggs,” Clarke said.

Conversations between the agencies and the GGSA continue into September with all attention focused on this fall season’s weather. Meanwhile, trophy fish are being landed just outside the protected 12-mile stretch of spawning grounds.

“The river is teeming with salmon,” said professional fishing guide Dave Jacobs, whose said his group landed several 15-25 pound Chinook salmon while he talked on the phone from his boat. “I saw 50 on the surface today.”

Jacobs, who frequently measures water temperatures while fishing, said the 54-degree water near the Keswick dam is perfect for spawning. However, 50 miles down river he recorded it as high as 64 degrees, two degrees higher than the GGSA had announced. The result: cautious optimism for the fall and late-fall runs.

“I do believe there is going to be cold water when the fall salmon come,” he said. “But it could be a lot warmer a month from now. That’s still to be seen in October.”

The Keswick Dam is the northernmost boundary of the salmon spawning area. Fishing is banned all year round at the dam. The stretch of the Sacramento River from the dam to the Deschutes Bridge, a landmark river crossing about 12 miles south of Redding, constitutes what is left of the Chinook’s historic spawning grounds. Two of the Sacramento’s four distinct salmon runs — the winter and spring Chinook —are protected and listed as threatened under the Endangered Species Act.

California’s salmon industry is a $1.4 billion enterprise that employs over 20,000 workers annually. The historic spawning grounds for the fish in the Sacramento River have continually diminished since the 1940s due to the construction of the Shasta and Keswick dams.

In March, another inter-agency government effort transported 30 million Sacramento River salmon smolts to the ocean by truck to help the fish avoid harmful river conditions caused by the drought. It is unclear if such a plan will be repeated in spring.

Ted Andersen is a reporter at the UC Berkeley Graduate School of Journalism. This story was produced as part of a J-school class focusing of environmental issues in the Bay Area.

Bay Area Seal Researchers Travel the Pacific to Save a Species

I

t’s early July, and aboard the battleship-like research vessel Hi’ialakai, National Oceanic and Atmospheric Administration (NOAA) scientists are returning from a 26-day search near Midway Island for distressed Hawaiian monk seals. The mission was a success as the ship now transports four underweight juvenile Hawaiian monk seals 1,500 miles to the Big Island for care. The two yearlings, nicknamed Hāla‘I (calm) and Maka‘ala (alert), along with two weaned pups Kūlia (to strive) and Ikaika (strong), would not have survived without help. Fewer than one in five monk seal pups will make it through their first year, according to NOAA.

Waiting to greet the young survivors were researchers from The Marine Mammal Center (TMMC), whose pioneering work on California seals and sea lions during the past four decades has given rise to a collaboration with NOAA in Hawaii. The partnership culminated at the beginning of the month with the grand opening of TMMC’s new $3.2 million Ke Kai Ola Hawaiian Monk Seal Hospital located near Kailua-Kona, on the Big Island, the only facility in the world dedicated to treating and protecting the Hawaiian monk seal.

“We are proud of what we’ve accomplished,” says Jeff Boehm, the center’s executive director. “We are doing nothing short of trying to save a species.”

The young seals became the first patients at Ke Kai Ola, which means, “The Healing Sea.” In addition to its strategic location near a marina and airfield, the 10-seal-capacity facility features well-ventilated pools for both mature animals and juveniles while offering shade, life support systems, water filtration pumps, a laboratory, a food-preparation area and a medical procedure room. It was fully funded by a combination of gifts from individuals and foundations, including donations from the Walnut Creek-based Firedoll Foundation. The lead donor wishes to remain anonymous.

The rescue and rehabilitation partnership comprises the most dedicated monk seal researchers in the world. The hospital will serve as a hub for visiting experts from Europe who likewise seek to protect the Mediterranean monk seal, the only other living species of monk seal, with only 600 individuals remaining. A third member of the family, the Caribbean monk seal, was last spotted in the 1950s and was officially declared extinct by NOAA in 2008 after an extensive five-year search.

“This is a real game-changer,” says Trevor Spradlin, a marine mammal biologist at NOAA’s Office of Protected Resources. “This is why the opening of the hospital is so important. We’ve already lost the Caribbean monk seal species. We’ve only got two left.”

monk seals in pool
Hawaiian monk seal pups Ikaika and Kūlia rehabilitate at The Marine Mammal Center’s Ke Kai Ola Hawaiian Monk Seal Hospital. (Photo courtesy of the Marine Mammal Center)

T

he Hawaiian monk seal gets its name from the short hairs on its head — its skullcap coif — that is said to resemble the do of a religious ascetic. Hawaii’s official state mammal since 2008, the seal is one of the rarest ocean mammals in the world and the only one native to the Hawaiian Islands. The monk seal is also the world’s only tropical pinniped. The population of monk seals, especially juveniles, has diminished over the last several decades due to hunting, overfishing, entanglement in ocean debris, and the rise of predators such as the Galapagos shark. They are now dwindling at a rate of three to four percent each year.

Another Northern Californian ally of the Hawaiian monk seal is UC Santa Cruz biologist Terrie Williams. Williams has studied a pup, nicknamed KP2, in her UCSC lab for over five years and wrote a book about the experience entitled The Odyssey of KP2: An Orphan Seal, a Marine Biologist, and the Fight to Save a Species. Williams, who is currently conducting field research in the Amazon, responded to the news of the opening in an email from the field.

“The new hospital is a wonderful step in the right direction by helping to rescue animals that would otherwise die (every individual monk seal counts at this point), allowing us access to animals to learn about their biology, and providing outreach opportunities for involving local people,” she wrote. “That said, this is a proactive approach to help a species BEFORE it becomes impossible to bring it back from the brink of extinction. The more we all know in terms of the need of wild animals and how humans are impacting them, the more effective our conservation plans and management directions will be.”

This highlights another aspect of the conservation effort: education. According to NOAA’s Spradlin, there are two distinct populations of Hawaiian monk seals, those in the Northwestern Islands and those in the inhabited islands. While the population of roughly 900 seals in the remote archipelago is declining, the approximately 200 that reside on the main chain seem to be holding steady and even growing in numbers thanks to conservation efforts. This, however, has led to more direct run-ins between the mammal and humans.

“Sadly,” Spradlin says, “We’ve had people hurting the seal.”

A New York Times article last May detailed a string of mysterious murders of the animal perpetrated by humans. Thousands of dollars in rewards were offered for tips that could lead to an arrest, but the beatings and shootings continued.

On the flip side, when a monk seal pulls up to a beach populated with humans, an emergency response team will cordon off the animal with tape, a site that ironically draws tourists near the basking animal, though not close enough to touch it. But with the new hospital, volunteer partners on the ground can contact NOAA seal teams for quick-response air or sea transportation to Ke Kai Ola’s world-class facilities. In the battle to save the species, these small victories could signal a turning of the tide.

Long-term rescue numbers also show promise. According to NOAA statistics, up to 30 percent of Hawaiian monk seals are alive because of recovery projects over the years.

“That tells us our efforts have been working,” Spradlin said. “Hopefully, [Ke Kai Ola] will make that 30 percent even greater. We are looking at this as a long-term goal.”

As for the hospital’s first patients—Hāla‘I, Maka‘ala , Kūlia, and Ikaika—their stay at Ke Kai Ola came to an end in late August. Their rehabilitation complete, they were transferred to a NOAA ship, which transported them 1,500 miles back to their homes for a second chance at life. On August 31, with their bellies full and bodies nourished back to health, they were released back into a world of no guarantees.

Ted Andersen is a reporter at the UC Berkeley Graduate School of Journalism. This story was produced as part of a J-school class focusing of environmental issues in the Bay Area.