Science Spotlight

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  • July 18, 2019

Three urchins attached to kelp various kelp stalks underwater. Urchins cover large rock in background.
Purple urchins grazing a desolate kelp forest, Fort Ross, 2015. (Photo credit: A. Weltz)

Several urchins clustered together covering large rock underwater with kelp stalk
Purple urchins consuming bull kelp fronds and stipes and crowding out native red urchins and abalone.

Several urchins and single abalone attached to kelp stalks underwater with large rocks in background
Unusual photo of abalone and purple urchins consuming bull kelp stipes. (Photo credit: A. Maguire)

Several urchins and single abalone covering large rock underwater
Large aggregations of purple urchins are wiping out kelp forests, creating pink barrens and out-competing other species, such as abalone, for food. (Photo credit: A. Maguire)

Rocky beach along rocky cliff side with two people in background and kelp in foreground laying on rocks.
Aftermath of the harmful algal bloom: dead abalone and other invertebrates washed up on shore at Fort Ross in 2011. (Photo by N. Buck)

Abalone turned upside down
Shrunken abalone due to lack of food, October 2015. The foot (meat) of the abalone should be roughly the same size as its shell. (Photo credit: S. Holmes)

The view of northern California’s beautiful coastline has historically been pristine and breathtaking. With dense kelp forest canopies blanketing the surface of the nearshore areas and protecting the abundant rockfishes, red abalone, sea stars and red urchins that lived below, it was a healthy, natural ecosystem rich with thriving inhabitants. Unfortunately, the ocean is now changing, and this idyllic scene is no more. But California Department of Fish and Wildlife (CDFW) marine scientists, citizen scientists and grassroots groups are all coming together to help turn back time.Their immediate focus is to eradicate the ever-increasing purple urchins.

For thousands of years, canopies of thick bull kelp (Nereocytis luetkeana) could be found along the coast of northern California, creating a rich subtidal home for the many fishes and invertebrates that lived and thrived in this region of the state. Today, bull kelp forests should be the foundation of our nearshore coastal ecosystem. The floating canopy of this brown algae gives shelter to young fish and sea stars, and the kelp itself provides food for valuable species, such as red abalone and red sea urchin.

Unfortunately, with the warming and changing ocean conditions in the last few years, scientists have noticed an alarming decline in these once prolific kelp forests. Though annually variable, in the just past five years, California’s kelp forests have declined by 93%.

In 2013, a mysterious wasting disease wiped out a large portion of the local sea stars in northern and central California. As a result, purple urchin populations exploded in the absence of the sea star, their main predator.

By 2014, a large patch of warm water developed off the coast, creating a catalyst that has further changed this underwater environment. The persistent warmer sea temperatures stress the kelp forests to the point that growth and reproduction have slowed dramatically and caused damage to remaining fronds and tissue.

But perhaps the most critical effect is that the purple urchin populations now thrive without their primary predators, and are left to graze the kelp unchecked. Purple urchins feed mostly on algae (like bull kelp) with beaks so strong that they can chew on everything from barnacles to calcified algae.

Along the north coast, purple urchins are now successfully outcompeting red urchins and abalone. The purple urchin population is now 60 times higher than normal. The areas that are now overrun by sea urchins with hardly any kelp left are referred to as “urchin barrens,” a type of ecosystem largely devoid of the biodiversity that used to flourish there. Due to this abrupt change, the seafloor now looks more like an underwater desert dominated by sea urchins, with little else alive.

“To address the impacts of the massive marine heat wave and kelp deforestation on the north coast we are going to need to shift our priorities and resources and come up with creative solutions,” says Dr. Laura Rogers-Bennett, a CDFW senior environmental scientist specialist based out of the Bodega Bay field office in Sonoma County. “I am encouraged that so many people and organizations are coming together in the Kelp Ecosystem and Landscape Partnership for Research on Resilience (KELPRR) collaborative and the "Help the Kelp" Campaign to promote kelp restoration in support of our kelp forest ecosystems and the human communities that make their living from the ocean.”

These negative effects reach from the ocean to the shore. Red abalone have been severely impacted by the loss of kelp and thus lack of food, causing the abalone fishery to close until at least 2021. Sea birds and marine mammals are also feeling the effects. With fewer fish available, the birds do not have enough food to feed their chicks. Reports indicate that 80% of black oystercatcher chicks and 90% of the local cormorant chicks are failing to survive. Harbor seals and sea lions are also hungry and feeling the effects.

In an all-out effort to address this devastating ecosystem change, scientists, management agencies and citizen scientists are all joining together to do everything they can to help. Their strategy is to harvest the purple sea urchins by hand to remove them from invading all of the substrate where bull kelp resides. By doing this they hope to create a network of healthy kelp patches along the coast.

Work is underway to create kelp refuge sites in North Caspar Bay, Noyo Harbor and Albion. This urchin removal project is a massive undertaking. Scientists hope also to try to develop commercial uses of the purple urchins, thus ensuring long-term sustainable harvesting.

Watermen's Alliance, a union of spearfishing clubs throughout the state, is coordinating urchin removal events this summer along the Sonoma and Mendocino coast using recreational divers wishing to assist with the purple sea urchin removals.

Next up will be the July 27-28 Purple Urchin Removal Event on Noyo Beach in Fort Bragg. They will need as many free divers and scuba divers as possible to participate, as well as kayakers to ferry full collection bags from the divers to boats and empty bags back to the divers. Just bring your dive gear or kayak gear and a valid California fishing license if you will be a diver removing urchins.

If you dive, boat, kayak or are just interested in helping, please contact the Noyo Center for Marine Science or Josh Russo with Waterman’s Alliance at (707) 333-9575 for details.

For more information about how to get involved, and stay up to date on kelp recovery efforts, please visit the following links. There are many opportunities for involvement, whether you are a scuba diver, freediver or just a concerned community member!

  • ReefcheckCA - volunteer to help monitor coastal ecosystems
  • “Help the Kelp” Program - Noyo Center for Marine Science
  • Watermen’s Alliance - advocates for clean, productive and sustainable fisheries.
  • Urchinomics: Focused on development of a commercial market for the purple urchin

Please join us for the next installment of the Conservation Lecture Series, “The Perfect Storm: Multiple Climate Stressors Push Kelp Forest Beyond Tipping Point in Northern California” by Dr. Laura Rogers-Bennett on Thursday, July 18 from 1:00 – 2:30 p.m. Dr. Rogers-Bennett will talk about the catastrophic decline of the kelp forests and the ecosystem it supports, including the red abalone and sea urchin fisheries, and the effects of climate stressors on northern California kelp forests. Register at www.wildlife.ca.gov/Conservation/Lectures.

This lecture will be held by webcast only. Members of the public can sign up using this registration link. For more information, please contact Whitney.Albright@wildlife.ca.gov or visit the Conservation Lecture Series website.

CDFW Photos. Top Photo: Unusual foraging behavior near Elk in Mendocino County: a large red abalone climbing a bare kelp stalk trying to reach fronds that are not there. (K. Joe)

Media Contact:
Carrie Wilson, (831) 649-7191

Categories: Wildlife Research
  • March 7, 2019

Man wearing beige fishing hat, khaki pants, white long sleeved shirt, and backpack on rocky slope holding round red item
David Wright uses a mirror to reflect light into dark rock crevices in search of pika sign such as scat or urine stains. CDFW image by Joseph Stewart.

Large sheer rock mountainside with snow at peak and some trees. Man standing on rock appearing very small compared to the mountain.
Joseph Stewart hikes through one of the mountainous locations in the northern Sierra Nevada that researchers searched for habitat that appeared suitable for pikas. CDFW image by Johanne Boulat.

CDFW staff recently conducted a study to determine whether American pika in California are able to find sufficient refuge from elevated temperatures in their natural habitat. Previous CDFW collaborative research and related work has suggested that pikas in California and Nevada have been declining in warmer areas, but some scientists contend that underground temperature refuges will protect pikas from warming temperature trends.

“The question of whether pikas are protected or exposed to warming temperatures seemed key to us,” said David Wright, a retired CDFW senior environmental scientist who co-authored the research with Joseph Stewart, a former CDFW scientific aid and now a University of California, Davis post-doctoral researcher. “It is central to whether or not climate change is going to push pikas to higher, cooler elevations and significantly reduce and fragment their range, in our state, on our watch.”

Pikas are small herbivores related to rabbits that live in fields of broken rock (talus) in the mountains of western North America. Researchers examined 46 mountainous locations in the northern Sierra Nevada with habitat that appeared suitable for pikas.  

Pikas prefer talus with rocks eight inches to three feet in size, and larger or less isolated talus fields are generally more likely to support pikas.

“We did our research at elevations both within and below the expected elevation range of pikas,” Wright said. “Lower elevations on average have warmer temperatures, which pikas don't tolerate well, but it's been suggested that talus provides a refuge from warmer temperatures. We wanted to look at this hypothesis.”

Two species of pika occur in North America, with only the American pika found within the continental U.S. With their high metabolic rates and thick fur (including inside their ears and on the bottoms of their feet), American pikas are well adapted to cold temperatures at high elevations. They do not hibernate during the winter, and spend the summer gathering grasses and wildflowers to store in “haypiles” for subsistence during the winter. Hikers may know them from their distinctive alarm call, a high-pitched cross between a chirp and a bark.

In 2010 to 2013, using small, year-round temperature recorders lowered approximately 1.6 feet to 3.3 feet into talus, along with visual surveys for pikas or signs of pikas, Wright and Stewart found that temperatures below the talus surface were buffered from warm and cold extremes of ambient air temperature. This was consistent with previous findings.

However, pikas were not found wherever talus temperatures were suitable. Temperatures within talus were mostly suitable for pikas across all the study sites regardless of elevation, yet pikas were absent from many of the sites. Instead, summer air temperatures proved to be the best predictor of pika presence or absence. The warmest sites had no evidence of pikas, followed by warm sites that had only remnant fecal pellets (pika pellets can persist among the rocks for decades), then slightly cooler sites that supported pikas in some years but not in others, to the coolest sites which supported persistent populations of pikas throughout the study.

“It’s not enough to have suitable temperatures in their underground burrows,” said Stewart. “Pikas also need suitable temperatures above ground where they forage for food.”

The authors concluded, based on their own and other research, that daily warm air temperatures may inhibit pika foraging and survival because they cannot tolerate the heat, and juvenile survival and dispersal may be similarly impaired by elevated summer high temperatures. Talus provides a cool refuge for pikas up to a point, but beyond that point pikas still need to forage and complete the portions of their life cycle that occur aboveground. This balance point, from this research, appears to be near an average warm season (June to September) air temperature of 71 to 73 degrees.

Funding for this research and similar CDFW efforts in the Sierra Nevada are supported by State Wildlife Grants administered through the U.S. Fish and Wildlife Service.

link opens in new windowThe study, Within-talus temperatures are not limiting for pikas in the northern Sierra Nevada, California, USA, can be viewed here (PDF).

CDFW Photos. Top Photo: Pikas are small herbivores that live in fields of broken rock (talus) in the mountains of western North America. CDFW image by Jan Dawson.

Media Contact:
Kyle Orr, CDFW Communications, (916) 322-8958

Categories: Wildlife Research
  • February 1, 2019

Concrete fish ladder along hillside and river. Hills in background.

Blue sign with red spray-painted text reading 'house spawning'

Fish splashing in water between gate and metal examination chute.

Two people in yellow rain jackets in hatchery facility alongside fish chute filled with fish.

At Iron Gate Hatchery in Hornbrook, the fall 2018 spawning operation has just concluded. Iron Gate spawns both Fall-Run Chinook Salmon and Coho Salmon from the Klamath River. For Chinook, the hatchery staff manually collect the eggs and mix it with the milt immediately after the fish come into the facility. CDFW environmental scientists also collect heads from adipose fin clipped salmon, in order to retrieve implanted tags in the snout. The retrieved tags tell the biologists which hatchery the fish is from, and when it was released. They also collect scales, which enable them to determine the age of the fish.

For Coho Salmon, the process is a little more involved. The Coho are measured and samples taken, but the samples are sent off to a National Oceanic and Atmospheric Administration (NOAA) laboratory in Santa Cruz for analysis. While the samples are processing, the fish are kept in individually-numbered holding tubes at the hatchery. They will be spawned after the tissue analysis determines which fish are the best genetic match.

CDFW Photos

For more information about Iron Gate Hatchery, please visit: www.wildlife.ca.gov/Fishing/Hatcheries/Iron-Gate.

Media Contact:
Kirsten Macintyre, CDFW Communications, (916) 322-8988

Categories: General
  • December 14, 2018

Brown haired woman wearing glasses, white laboratory coat and white gloves in front of machine in laboratory
Kelly McCulloh loads evidence samples onto a DNA extraction robot.

Brown haired woman in white laboratory coat and white gloves holding pipette standing at counter in laboratory
Jillian Adkins prepares samples for DNA extraction.

Brown haired woman in white laboratory coat and white gloves sitting at desk with microscope and small tool in hand.
Erin Meredith uses a dissecting microscope to isolate hair roots for nuclear DNA extraction.

Long haired woman in white laboratory coat and blue gloves standing at laboratory machine with glass window partially lowered.
Ashley Spicer prepares a Polymerase chain reaction used in DNA sequencing.

If they weren’t so busy or their work wasn’t so mission-critical, you might find CDFW’s Wildlife Forensics Laboratory team on loan to the California Department of Education.

The four-person scientific team is all women with undergraduate and advanced degrees in biochemistry, genetics, molecular biology and forensic science.

Jillian Adkins, Kelly McCulloh, Erin Meredith and Ashley Spicer would be stars of state education initiatives to attract more girls to STEM (Science, Technology, Engineering and Mathematics) fields. They would be celebrated at school tours, asked to provide their personal stories at education conferences and inspirational messages in science classrooms across the state.

Instead, this team works mostly out of the spotlight, their scientific analysis critical to CDFW’s law enforcement mission to protect California’s natural resources and provide public safety. Increasingly, CDFW’s Wildlife Forensics Laboratory is being counted on to protect some of the most sensitive animal species on the planet.

“We just don’t lose these cases supported by forensic evidence. It’s amazing,” said Tony Warrington, a recently retired assistant chief who has managed CDFW’s crime lab for more than a decade. “Our forensic specialists do a fantastic job utilizing advanced scientific methods to support wildlife officers with poaching investigations and public safety wildlife incidents.”

Meredith, a senior wildlife forensic specialist with nearly 20 years at the lab, said the mere suggestion by a wildlife officer of sending evidence in for DNA analysis will sometimes prompt poachers to confess to their crimes. The lab is one of only about 10 wildlife forensic labs in the nation, giving CDFW wildlife officers a major crime-fighting assist. Every CDFW wildlife officer can access the lab, which processes evidence in about 100 criminal cases every year.

The white lab coats, antiseptic setting, high-tech equipment and talk of DNA sequencing invite comparisons to “CSI” – Crime Scene Investigations – the long-running night-time television drama that firmly implanted forensics in the public consciousness.

“My joke is always that human forensics is boring – you only work on one species,” Meredith said. “With wildlife, the possibilities are essentially endless.”

First established in the 1970s, CDFW’s Wildlife Forensics Laboratory has taken on a more prominent role with advances in genetic research and technology and the widespread acceptance of forensic evidence in the court system.

“If there’s blood on a knife, not only can we tell whether it’s from a deer, we can also tell whether it’s from a doe or a buck,” Meredith said. “We can tell if the blood on the knife originated from the same deer or evidence taken from a kill site or meat in a suspect’s freezer.”

Said Adkins, “DNA evidence has been a game-changer in determining guilt or innocence – in both people and wildlife.” Adkins’ work in providing quick turnaround of DNA samples allows wildlife officers to use the results to make critical enforcement decisions.

CDFW’s Wildlife Forensics Lab plays a key role in public safety and animal attacks that may involve great white sharks, coyotes, bears or mountain lions. With even minimal DNA evidence, offending species and animals can be identified with certainty in most instances.

“We literally free the innocent – and it’s happened a number of times,” Meredith said. “Our wildlife officers may trap what they think is the guilty bear, draw its blood and bring it to the lab for comparison with saliva from a bite wound or even a scratch mark on the victim. And if that DNA is not a match, that bear gets released.”

Retired assistant chief Warrington said, “This lab completely changed the way we deal with public safety wildlife. DNA matching has allowed CDFW to protect the innocent and positively identify the offending animal in these cases – a big step forward in protecting California’s wildlife.”

The lab marked another milestone in 2015 with the adoption of Assembly Bill 96, which closed a loophole in the state’s ban on ivory and made it illegal to purchase, sell, possess with intent to sell or import with intent to sell ivory or rhinoceros horn – with limited exceptions.

The legislation tasked a state wildlife agency with helping to combat the global ivory trade in order to protect ivory bearing species from poaching, exploitation and extinction worldwide. AB 96 provided funding for CDFW’s Wildlife Forensics Lab to add a fourth scientist in McCulloh.

McCulloh arrived with a master’s degree in forensic science from UC Davis. She has pioneered California’s genetics test for ivory products. It’s so accurate, it can distinguish African elephant ivory from Asian elephant ivory and even ivory from a long-extinct woolly mammoth.

Spicer, a native of British Columbia with degrees in biochemistry and forensic science, specializes in the physical characteristics of ivory that distinguish it among the many different ivory-bearing species – from elephant and hippopotamus to sperm whale and warthog – and also from non-ivory products such as synthetic ivory or plastics made to look like ivory. 
Spicer personally has worked on 17 of the 18 criminal ivory cases that have come through the lab since AB 96 was enacted. Her work has included serving as an expert witness and testifying at trial.

The lab’s contributions were link opens in new tab or windowheralded recently in the conviction of a Los Angeles County business owner on charges of selling two ivory tusks from Arctic narwhal whales. The tusks measured 79 and 89 inches long.

CDFW’s forensic scientists don’t necessarily mind all the newfound recognition – as long as the focus remains on their work.

Said Spicer, “We are really committed to the highest standards and ideals of science.”

YouTube Video Link: link opens in new tab or windowhttps://youtu.be/4KS4e3ILKOw

CDFW Photos. Top Photo: The four-woman forensics team.

Categories: Wildlife Research