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Sea Otter Savvy

Sea Otter Science And Community Outreach

Sea Otter Awareness Week 2021

Photo by Jeff & Wendy Photography

Photo of a mother sea otter wrapped in kelp with her pup by Jeff & Wendy Photography.

Annually, throughout the last week of September, we celebrate sea otters during Sea Otter Awareness Week. We encourage zoological and educational institutions, governmental agencies and communities to plan and undertake events that highlight sea otters. These activities include sharing stories, disseminating science and generating media that inspire a deeper awareness of these unique marine mammals, their ecological importance and the many challenges they face.

This year's Sea Otter Awareness Week's theme, Ecosystem Mosaic, follows the idea of the sea otter’s ecosystem as a mosaic of tiny parts in which the removal of key elements or damage to the system’s structure renders the ecological picture incomplete. 

SOAW fullLogo design by Heather BarrettThe Ecosystem Mosaic theme was inspired by groundbreaking research published by a collaborative of scientists from University of California Santa Cruz, the Western Ecological Research Center of the U.S. Geological Survey, and the Monterey Bay Aquarium in 2021. This large-scale study examined ecosystem complexity revealed by the catastrophic loss of an important kelp forest predator -- the sunflower star. The sudden shift in the web of organisms uncovered new insights into the functional role of sea ottes in California kelp ecosystems. Dr. Joshua Smith, the lead author of this study, will be a featured speaker leading off the week's exciting agenda of events.

A mosaic relies on each piece of tile to contribute to a complete image. Similarly, a thousand tiny elements must coexist to form an ecosystem. Removing pieces from a mosaic equates to losing vital components of an ecosystem. As more parts are removed, the value of the art or the ecosystem diminishes.

Sea Otter Viewing Stations

Throughout Sea Otter Awareness Week 2021 (September 19-25) you can meet volunteers from SeaLife Stewards, Sea Otter Savvy, California State Parks, the Elkhorn Slough National Estuarine Research Reserve, Defenders of Wildlife, Monterey Bay Aquarium, Santa Cruz Museum of NAtural History, and the Morro Bay State Park Museum of Natural History to learn about sea otters and experience wild sea otters from the best viewing locations in California. Volunteers will be ready to help you be expert otter spotters with binoculars and spotting scopes, answer your sea otter questions, and share how you can help protect sea otters! Click on the Sea Otter Awareness Week icons on the map below to find the station nearest you. Each location icon has a photo of the site and hours when volunteers will be present. 

Highlights of Sea Otter Awareness Week 2021

For a full list of the week's events, visit the Defenders of Wildlife Sea Otter Awareness Week page.

Float Down the Coast Livestream

Tuesday, September 21, 2021, 12:00pm - 1:00pm

Sea otter experts will report live from as far north as Washington or British Columbia and all along the California coast south to Baja to share some science and stories about sea otters. 

Look for this livestream on Sea Otter Savvy and CA State Parks' YouTube, Facebook, and Instagram. 

T-shirt fundraiser

Show off you sea otter awareness and support our cause by purchasing a t-shirt featuring the Ecosystem Mosaic logo! 

Fundraiser auction on eBay: Ecosystem Mosaic

Bid to win an original mosaic art piece by New World Mosaic's Juan Lopez. This peice was inspired by this year's logo and was custom made to commemorate the them of "Ecosystem Mosaic". Bidding on this striking art work will begin on September 19th and will run for 10 days. All proceeds will go to support Sea Otter Savvy in our mission to inspire stewardship of sea otters. 

Make your Ecosystem Mosaic!

Show us your creative side by entering the Ecosystem Mosaic Challenge! Download the template, follow the directions (be creative!), and share your masterpiece with @seaottersavvy in Facebook, Instagram, Twitter, or YouTube. 

Ecosystem Mosaic Challenge template and instructions

We Were Here Events

wwh 1Look for the tag #WeWereHere for events that are part of our We Were Here sea otter program.

The goal of the We Were Here campaign is to educate the public and stakeholders in the San Francisco, Northern California regions about the historical role of sea otters and their potential value to northern California ecosystems. With the focus of southern sea otter conservation and recovery efforts increasingly focused on population expansion beyond the current range limits, it is vital to start instilling a sense of stewardship and a desire for coexistence among coastal communities where sea otters may soon appear.

Visit the We Were Here page and take the survey to share your opinion about reintroduction as a strategy to reestablish sea otters in their historical range. 

The Sea Otter Awareness Week Planning Team

 

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The California Coastal Wildlife Distubance Symposium 2020: Reflections from attendees

By Jeff Torquemada and Wendy Sparks

What an exhilarating experience to spend two days with people who have a common passion ─ protecting coastal wildlife and their habitat. This statement, “ It is important to pair knowledge with emotional appeal” encapsulates so much of what was shared during the symposium and it served as the springboard for participants to generate creative ideas to promote and provide awareness and education to the public regarding best practices while visiting coastal wild places.

Participants in one of the 6th CA Coastal Wildlife Disturbance workshop groupsParticipants in one of the 6th CA Coastal Wildlife Disturbance workshop groups

It has become quite evident COVID-19 has had a significant impact on the number of people spending more time outdoors. They are “over-loving” national parks, state parks and coastal marine sanctuaries. In his presentation, State Parks Ranger Robb Mullins shared a number of dramatic examples demonstrating an increase in the number of poaching incidents of plant life and mollusks. The challenge for law enforcement is when to use the “spirit of the law” rather than the “letter of the law”.

Tidepool wildlife is being harassed and some people are doing dangerous and disrespectful stunts involving wildlife just to be a social media sensation. There is a need to “one up” one another on social media, which drives people to push beyond ethical limits to post a photo. This is also one of the causes of “bad behavior” in our parks, sanctuaries and reserves.

Can we use social media as a positive tool? There are Instagram accounts with huge followings such as the kayak fishing for beginner’s account. Messages regarding ethical practices could be posted on these types of sites and reach a larger and more diverse population. Getting a celebrity involved in awareness messages via social media would also reach far more people.

The ongoing problem of getting too close to marine mammals continues to be a challenge, but the collaborative efforts of local kayak and paddleboard businesses working in conjunction with Sea Otter Savvy has had a very favorable impact ─ gotta love those important baby steps!

shhh morro bay 500Simple signage in Morro Bay, CAIt was agreed, too many signs may cause sensory overload. However, visuals like the “Respect the Nap” plaque with the image of the sleeping sea otter makes a powerful statement with very few words. We actually have witnessed people viewing sea otters and then discussing that very powerful message. In Alaska we learned, there are signs educating boaters to give whales space. The simple statements, “Give Whales Bubble Room!” and “Don’t Burst My Bubble” educates with a touch of humor.

Two of our favorite presentations were Dr. Megan McKenna’s presentation on integrating sensory ecology into conservation. We know the animals returned to the Yosemite Valley during COVID-19  due the absence of humans and all noise we create!  Stanford University’s J P Spaventa’s presentation on testing sea otter responses to UAV’s was truly cutting-edge technology and would make data gathering more efficient and less stressful on wildlife.

Perhaps the most powerful discussion was recognizing that scolding people, who were doing something unethical, only has a short-term impact and most likely will not change that individual’s behavior. The two of us are guilty of admonishing a couple who was attempting to photograph a bobcat with an iPhone, while constantly yelling “Here, kitty kitty” every time the poor bobcat was ready to pounce and catch his next meal. Yes, we did go a bit “COVID Crazy” and the people did leave, but we should have walked over and explained to them they were interfering with an animal’s efforts to survive-it was a teachable moment and we blew it! We must remind ourselves to be ambassadors.

Maslow’s Hierarchy of Needs should serve as our guiding foundation as we work together to effectively bring about change. We want to plant seeds of awareness that touch upon people’s core beliefs or educate them in such a way our messages become their core beliefs.  Humor is a great tool to share an important message ─ the Respect the Tidepools from song is a perfect example of using humor, great visuals and a catchy tune to teach children how to safely and respectfully explore tidepools. These creative approaches to educate children about marine sanctuary awareness should be an integral part of the elementary school science curriculum. Children often teach adults valuable lessons about ethical behavior.

The quote below reflects the combined power and creative energy of the attendees at the Coastal Wildlife Disturbance Symposium. We are honored to have been part of this think tank.

“Never doubt that of a small group of thoughtful, committed citizens can change the world; indeed, it’s the only thing that ever has.”

                                                      -Margaret Mead

Jeff & Wendy


From the editor:

Videos of all the 6th California Coastal Wildlife Disturbance Symposium presentations can be viewed on the Sea Otter Savvy YouTube Channel.

Check out the resources pinned to the virtual bulletin board "Gallery of Ideas"! You can find absracts of presentations, review the agenda, and see videos, oureach materials, research articles and more, shared by symposium panelists and attendees. 

Read about past symposia:

4th Annual in 2018

5th Annual in 2019

Jeff and Wendy at workAbout the authors:

Jeff Torquemada and Wendy Sparks, aka Jeff and Wendy Photogrpahy, are passionate about preserving all things wild and through the medium of photography and have spent over 40 years and thousands of hours observing and photographing animals-always waiting to capture that perfect light! All of the animals in their photographs are taken in their natural habitat; they do not bait nor risk compromising the welfare of an animal just to capture an image.

Learn more about them by reading their blog on the ethics of photographing sea otters.

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Our Winning Wildlife Storytellers

Wildlife Storytellers First place winner, Respect the Nap, by Allison Gregor

The mission of the Wildlife Storytellers Photo Contest is to promote photography as a medium for sharing stories about the deep relationships between organisms and the places they live. More than portraits of individual species, winning photos will tell a story about the relationship between a species within the context of the habitat it lives in, to inspire a deeper awareness and appreciation for the conservation of intact ecosystems and biodiversity. We aim to transform this aspiration for eye contact portraits to those that celebrate ecosystems and capture meaningful images that tell the stories of animal life in wild places.

We’d like to congratulate the winners of this year’s Wildlife Storytellers contest and thank all of the participating photographers. We received excellent entries that promoted our mission for ethical wildlife photography while emphasizing ecological storytelling. We hope you enjoy the winning photographs and their unique stories.

First Place:  Allison Gregor with ‘Respect the Nap’

Southern sea otter, taken from a quiet nursery viewing area in Morro Bay approximately 30 ft onshore behind a barrier fence. Canon 7Dii at 600mm (equiv. to 960mm focal length), photo not cropped, Dec 25, 2019Southern sea otter, taken from a quiet nursery viewing area in Morro Bay approximately 30 ft onshore behind a barrier fence. Canon 7Dii at 600mm (equiv. to 960mm focal length), photo not cropped, Dec 25, 2019

On a visit to Morro Bay last year, I came across an area known to locals as "the nursery", a quiet area for groups of sea otter moms to sleep, eat and teach their pups the ways of the world. I have spent countless hours watching the interactions between mom and pup at that location. Sea otter moms rule!

After sea otters give birth at sea they become 24/7 caregivers over the next 6-8 months. Along the way, mom will teach her pup how to swim, maintain its fur and eventually how to forage for its food. Sea otter moms will have been pushed to their absolute limits by the time the pup is old enough to be fully independent. 

Did you know that non-nursing sea otters have to eat roughly 25% of their body weight per day? They have huge energetic requirements and need to consume large amounts of food. Unlike most marine mammals, sea otters do not have layers of blubber instead relying on their thick fur to stay warm. A lot of energy is used to maintain their fur as well as foraging for food. If they are nursing or caring for a pup, even more energy is needed and their daily food requirement can be twice as much as those without pups. Some sea otter moms can spend up to 14 hours per day foraging!

So, whenever you see sleeping sea otters, think of all they need to do to care for their pups. Any disturbance to their sleep can be detrimental, not only to the mom but to her pup as well. 

                                                        — Allison Gregor

Runner Up: Kathleen Curtis with ‘Panic of the King Tide’

Photo taken at 300+ meters with a Canon EOS Rebel T6S using a 210 mm telephoto lens. Photo taken at 300+ meters with a Canon EOS Rebel T6S using a 210 mm telephoto lens.

This photograph was taken at Piedras Blancas Elephant Seal Rookery, in San Simeon, CA in January 2019 during the King Tide-the highest tide of the year. This unfortunately coincided with a strong Pacific storm, covering the beach in surf. In this image, new born elephant seal pups are struggling to stay on the beach, while the raging surf pulls them out to sea. These young pups do not yet know how to swim and their blubber layer is insufficient for the cold water. This image captures their brave struggle to survive.

— Kathleen Curtis

Honorable Mention: Sharon Hsu with ‘Mom’s Home’

Moss Landing, CA, Canon EOS 7D, EF 100-400mm f/4.5-4.5L IS USMoss Landing, CA, Canon EOS 7D, EF 100-400mm f/4.5-4.5L IS US

A snowy plover makes its way back to her nest to incubate her eggs. One of the last nests of yet another difficult breeding season for these small shorebirds, extra efforts were made by conservationists to protect this particular nest. The breeding pair may have been first time breeders, as the nest was constructed in an exposed area of the beach, and unfortunately, a week after this photo was taken, the eggs were swept away by an unusually high tide. 

— Sharon Hsu

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Why Sea Otters Don’t Need Sunglasses or Swim Goggles

By Sarah McKay Strobel

Artwork by Will Bullas

When was the last time that you woke up thirsty in the middle of the night? Maybe you got out of bed and turned on the light. Groggy with eyes blinking from the brightness, you staggered to the kitchen. After drinking a glass of water, you turned off the light, but the hazy afterimages in your vision forced you to rely on your memory and touch to return to your bed. You might consider this scenario a minor inconvenience, but consider if you had to repeat this every three minutes for the next four hours? 

Sea otters run through this routine regularly, but instead of going to the kitchen for a glass of water, they dive 30 to 100 feet to find and catch an unsuspecting meal at the seafloor. Light attenuates more quickly under water than in air, so even if the sun shines brightly at the water’s surface, shallow-diving sea otters hunt in semi-darkness. Unlike seals, sea lions, and whales, sea otters do not eat under water, so they bring what they catch to the bright light at the water’s surface to process and consume. After a quick spin to wash off lingering debris from their hard-shelled invertebrate snack, sea otters dive back to the dim seafloor to search for the next bite. While sea otters may get a reprieve from stark light transitions between dawn and dusk, they still successfully forage, groom, and socialize in darkness throughout the night [1-3]. Prolonged seasonal shifts are a fact of life for sea otters in Alaska, who experience nearly 24 hours of daylight in the summer and about 18 hours of night in the winter.

strobel fig 1Caption: The tapetum lucidum in a young, female sea otter reflects the camera flash as a green-yellow circle within the pupil at dusk. The tapetum lucidum in the same sea otter viewed with a special camera reflects a gradient of turquoise, green, yellow, orange, and reddish-brown The presence of the tapetum lucidum in the upper portion helps reflect light from the lower visual field (as in human eyes, images are upside down on the retina and the brain flips the image perceived by the eyes). Researchers have been unsure how to interpret observations of wild sea otters in the context of vision for decades. Sea otter prey is often visually camouflaged or buried, and the digging methods that sea otters use to extract them can actually make the surrounding water cloudy [4,5]. However, some sea otters seem to seasonally shift their foraging activity to daylight hours [6], which suggests that vision improves sea otters’ ability to find and capture prey, thereby conserving energy. As the folks at Sea Otter Savvy can attest, sea otters are highly visually attuned to disturbances and direct their gaze toward the offender when deciding whether to settle back in for a nap or leave the area. 

So what is a sea otter to do? Vision takes a lot of energy to maintain, and researchers have consistently found that conserving energy is one of the top priorities that drives sea otter behavior.  Have sea otters reduced their reliance on vision or have they developed specialized visual adaptations that help them navigate a highly variable and wide-ranging light environment? 

Recent research by my team has helped to fill in longstanding gaps to help us answer these questions [7]. We examined how parts of the sea otter eye—the pupil, retina, and tapetum lucidum—contribute to vision. We found that the retina resembles those of other nocturnal mammals with a dense array of photoreceptors (light-sensitive cells) that is heavily dominated by highly light-sensitive rods. Sea otters have a well-developed tapetum lucidum (Latin for “bright tapestry”) at the back of their eye, which acts like a mirror to reflect light to the retina. Humans and other primates do not have a tapetum lucidum, but it causes the eyeshine you notice in your dog or cat at night. Together, these findings indicate that sea otter eyes are sensitive enough to see reasonably well in bright light and low light, both in air and under water. 

strobel fig 2Size range of the circular pupil in an adult, male sea otter, photographed across day (left photo) and night (right photo). The scale bar in the upper-right-hand corner represents 1 mm.Sea otter pupils are highly mobile in size, but not as much as seals and sea lions [8], and the pupil’s constriction response is slightly slower than in other species measured [9-11] . Just like a camera’s aperture, the pupil’s size and shape determines how much light is transmitted to the lens then refracted to the photoreceptors and tapetum lucidum. These observations suggest that although sea otters can see over a wide range of light levels, they may be limited in adjusting to the rapid and extreme change in light conditions when diving during the day. 

However, sea otters’ ability to see across a wide range of light levels doesn’t necessarily mean that sea otters see clearly across light levels. When sea otters rest at the water’s surface, their eyes focus light the same way as human eyes: light bends as it travels from the air through the eye due to differences in optical density. When light bends just the right amount, it converges at the photoreceptors on the retina, resulting in a clear image. Even if you have clear vision in air, have you ever tried opening your eyes under water in a swimming pool and noticed that your vision is blurry? Since the optical densities of water and your eye structures do not differ much, light bends less as it passes through the eye. The result? Light converges behind the retina, resulting in a blurry image. Swim goggles remedy the blurry image for humans, since light travels through the air in the goggles before reaching the eyes. 

strobel fig 3Special staining techniques help us to better visualize the sea otter retina, in which the photoreceptors resemble a galaxy of colored stars! Highly light-sensitive rods (in blue) dominate the retina relative to cones (in green).In ideal conditions in air, sea otters can see about as clearly as seals, sea lions, and walruses [12-22], which is about 7x less clear than humans with 20/20 vision. If you are near-sighted, and your prescription is between -2.00 and -3.00, a sea otter may see about as clearly as you do without your corrective lenses (although keep in mind this is a very rough approximation). We have evidence that sea otters see just as clearly under water as they do in air [23], so what is the sea otter version of swim goggles? Sea otters can squeeze their lenses through their pupils into a more rounded shape when diving [23]. The more rounded shape bends the light more, which compensates for the reduced bending effected by water, and light properly reaches the retina, enabling a clear image. Although humans can change the shape of our lens when focusing on near and far objects (termed accommodation), our abilities and those of most other vertebrates measured are nowhere near as impressive as sea otters. In fact, sea otters have one of the highest accommodations measured in vertebrates, rivaled only by freshwater otters and diving birds like cormorants [24-27].

Since the pupil plays a key role in reshaping the lens of sea otters when under water, what happens to sea otter vision during low light levels when the pupil dilates to capture more light for the retina? Similar to trying to blow a bubble with an open mouth, if the lens is squeezed through a wider aperture, it will be less round and bend light less, resulting in a blurry image. This means that the sea otter version of swim goggles only works to produce a clear image under a narrow range of light levels.

Darkened daytime conditions like those experienced during California's 2020 wildfires may have triggered sea otter nighttime foraging superpowers. Photo by Sharon HsuDarkened daytime conditions like those experienced during California's 2020 wildfires may have triggered sea otter nighttime foraging superpowers. Photo by Sharon HsuSo, how does the combination of pupil, lens, photoreceptors, tapetum lucidum, and accommodation all factor into the visual world of wild sea otters? In air, sea otters likely use vision during the day in social interactions and to detect and avoid dangerous situations. Even though sea otters don’t have highly acute vision to resolve fine detail, they can likely ascertain danger based on contrast due to brightness or color differences (yes, sea otters can see color [28], similar to a red-green colorblind human!. Current predators of sea otters, including bald eagles, coyotes, and brown bears, tend to hunt diurnally from air or land, as did a former predator of sea otters—humans—prior to the last century [29-31]. When foraging under water, sea otters surely use vision during brighter light to detect non-buried prey and associated environmental features, and they may use vision in dimmer light to detect large environmental features associated with prey. However, sea otters are unlikely to use vision in low light to detect non-buried prey or fine details of the underwater environment. 

Like all living organisms, sea otters are not restricted to a single sense for any one behavior. We’ve known anecdotally for decades that sea otters can compensate for vision loss, since they can forage just as successfully during low-light levels and periods of poor water visibility, and when hunting for buried prey. Recent research has confirmed that this ability likely results from highly sensitive whiskers and paws, which can discriminate fine detail as well as humans and other touch specialists, but incredibly faster [32].

We still have so much to learn about sensory biology and its influence on behavior, not only in charismatic marine mammals like sea otters, but also in species less traditionally considered just because they seem very different than humans. All kinds of life—from insects to plants to bacteria—use some form of light, sound, chemicals, touch, electricity, and/or magnetic fields to survive. Examining sensory abilities across diverse life forms reminds us that what we humans consider as objective aspects of this world, based on how we view, smell, feel, and hear, are in reality the most inherently subjective concepts of all.

 

About the author

strobel biopic 2Sarah McKay was born and raised in Nashville, Tennessee (which explains why she has two first names), and she recently graduated with her PhD graduate in Ecology and Evolutionary Biology from the University of California Santa Cruz (UCSC). Her dissertation research investigated how sea otters detect, locate, and acquire benthic prey in controlled and natural settings. Sarah McKay is broadly interested in sensory ecology, neurobiology, and behavior of amphibious animals. As she continues to advance her research, she is also committed to improving equity in science and academia—she currently works as a program coordinator for STEM undergraduate tutoring services at UCSC. If you want to stay up to date with Sarah McKay’s research (and watch her learn how to tweet), please follow her on Twitter

When not in the midst of research or program coordination, Sarah McKay thrives on being outside as much as possible, rain or shine, and she enjoys pushing her body with activities like rock climbing, yoga, trail running, and mountain biking. She readily admits that she has zero self-control around a bag of cheesy popcorn, and she is finally making some progress with training her rescue german shepherd dog to realize that other dogs aren't so scary.

References

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