Adventures in Mexico 2018: Vivan los Aves!

By Nikki Inglis, visiting student of California State University Monterey Bay

Photos by Nikki Inglis unless otherwise indicated.

It wasn’t until the last star came out on moonless night that we heard it. At first, it sounded like the incessant wind whipping around the wooden cabin walls. Then we heard it again; a growling rasp, a ghostly whisper and so, so close. We heard wings gliding in from the Pacific Ocean and a welling up of some invisible kind of energy.

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Ninety-five percent of blackvented shearwaters nest on Isla Natividad, Baja California Sur, Mexico. © Greg Gilson 2014.

Within minutes, the sound was everywhere. The hills teemed, wings flapped frantically around us. We couldn’t see any of it, but the soundscape was three-dimensional, painting a picture of tens of thousands of birds reveling in their moonless refuge. Isla Natividad’s black-vented shearwater colony had come to life.

We had been on the island for seven days and not heard a peep. Only two shearwaters had been spotted by our group - birds that had been trapped by daylight and forced to wait it out in hiding. I was starting to wonder if perhaps they hadn’t arrived yet, and only a few early-breeders were scoping out their seasonal nesting grounds. I tried to imagine what 70,000 birds might feel and sound like, but I never imagined this. The black-vented shearwater colony on a moonless night is a singular experience, but it’s not the only reason bird researchers and enthusiasts are interested in Isla Natividad. This remote desert island is a haven for seabirds and houses a myriad of rich desert habitats—largely free from human disturbance—that offer fascinating insight into distributional patterns, morphology and behavior of familiar and uncommon species.

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Nesting black-vented shearwaters

Ninety-five percent of the world’s black-vented shearwater population nests at Isla Natividad. The shearwater colony covers about 2.5 sq. km. on the southern tip of the island, surrounding the town center and lining most of the roads on the island. You can hardly take a step without running into a shearwater nest, so those steps must be taken carefully. Walking off trail is strictly forbidden, and even headlamps at night are discouraged in observance of the bird’s extreme and almost pitiable sensitivity to light. Recent aerial surveys indicate that there are about 35,000 nesting pairs of shearwaters on the island each breeding season, which runs from March to August. On Natividad, the locals call them “los nocturnos.” The locals’ pride over the nocturnos is contagious. They are adamantly protective over the colony, and there’s even a shearwater mural in town emblazoned with the words “vivan los aves.”

The nocturnos are so sensitive to light that even bright moonlight will keep them underground or out on the water. Wait for a waning moon—when the sun sets before the moon rises—and sit on a dark beach. It’s worth a trip to the island just for a brief window of moonless night to wander through the otherworldly din. Quiet just won’t sound the same afterwards.

Other seabirds

If the awe of the shearwaters’ immense but invisible presence wears off—and it might not—the island’s other bird-related curiosities offer endless exploration.  I see massive flocks of brants offshore. Divers on the boats that rounded the northern tip of the island noted double-crested cormorants on the rocky cliffs. Brown pelicans strut indignantly around beaches and glide in squadrons over breaking waves. At one time, least and Leach’s storm petrels nested here. It’s still unknown if they’ve returned since nonnative threats (ie, feral cats) have been eliminated. Researchers are also interested in whether Xantus’ or Craveri’s murrelets are nesting there now.  Circumnavigation of this wild island by panga could definitely yield some notable sightings to any intrepid birder.

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Isla Natividad’s Western gulls are an integral part of island life and have distinctly strong personalities.

Shorebirds

The sunrise casts a pink tinge on the tide’s fizzy froth. With each ebb and flow, a flock of plovers forage in the wet sand, scattering as the water nips at their feet.

I spent several afternoons in the intertidal, where I watched great egrets forage in tidepools draped in kelp, and whimbrels sink their long beaks in the sand. I spotted a tri-colored heron, another bird for my life list, as they don’t make it much further north than this. There are several species and variations thereof on Natividad that can’t be found in central California.

There is a notable pattern in bird ranges in which some species from the east coast of North America snake around through the Gulf of Mexico and pop up over in the Gulf of California and the west coast of Baja, but rarely make it into southern and central California. For example, this pattern is why, on Natividad, the oystercatchers have white bellies. They’re American oystercatchers, and they’re commonly seen in the on east and southeast coasts. But further north in alta California, the black oystercatcher takes over. True to its name, it’s solid black as night. It’s perplexing, as the ecology of Baja’s pacific coast is much more similar than to California is to that of the Gulf of Mexico.

It almost seems as if some of these birds observe the U.S.-Mexico border, and want to avoid the Tijuana traffic as much as we do.

 

 

Desert birds and raptors

Ospreys rule the island. Nests occupy almost every power pole in town. During our visit, one osprey nest between the store and the laborotorio, was a constant source of entertainment. Mom, dad and two fledglings lived out a mini reality show that featured nest-building, the occasional argument and one confused teenager on the ground looking up at his nest in frustration.

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Horned larks are abundant in inland habitats on Isla Natividad.

Away from shore, the seemingly barren scrub and cactus forests come alive with lark songs. The horned lark will look familiar to California birders. Petite but statuesque, these songbirds are instrumental in the desert soundscape, balancing out the honks of the seagulls with their delicate tune.

Ravens patrol the skies over the island, roosting ominously at the lighthouse, making bold, throaty calls and sending the resident rodents cowering in their burrows.

Pack your binoculars and field guide and make the walk up to the lighthouse that crowns Isla Natividad. On the short hike, you’ll pass through seagull colonies and be subject to their insistent harassment. You’ll watch hunting raptors rocking in the sea breezes. You’ll see blue water in every direction and the flocks of seabirds beyond the breaking waves. And you’ll understand why these creatures fly so far just to be here.

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Skulls and corpses are often the only signs of black-vented shearwaters during daylight hours. But on a moonlit night, the colony comes to life.

Environmental Changes are Influencing Individuals, Not Just Populations

By Abram Fleishman, San Jose State University graduate student

Each December my news feeds, from Facebook and Twitter to professional listservs and
mainstream news sources, are inundated by a flood of stories about one bird. Not one
species of bird, but actually a single individual living on one of the most remote islands in one of the most remote archipelagos in the world. A bird that if it was not beautiful, elegant, and most of all old, no one would care about.

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Wisdom preens her freshly-hatched chick on Midway Atoll. (Photo: Naomi Blinick)

Wisdom is a Laysan Albatross that nests on Midway Atoll at the far end of the Hawaiian
archipelago. While part of Hawaii, this is not the tall volcanic tropical paradise you picture when your friend tells you she is going on vacation. Midway is halfway between North America and Japan, an ancient sunken island that now only scratches the surface of the Pacific. Once a bustling military base during WWII, Midway is now a wildlife refuge and home to several million seabirds.

Wisdom was first banded in 1956 by a biologist named Chandler Robbins as part of the Pacific Biological Survey (see her profile here). She was banded as an adult, which means her exact age is not known, but because Laysan Albatrosses do not nest until they are ~5-8 years old, she is at least 66 years old. This makes Wisdom the oldest wild bird ever recorded, which has been the focus of much of the press that she has received. Perhaps just as interesting and impressive is that she has been laying an egg each year (albatrosses only lay a single egg) and even hatched a chick this year at age 66! Her life has been heavily chronicled by researchers, and you can follow along here.

Recently, at the 43 rd Annual Meeting of the Pacific Seabird Group in Tacoma, Washington, I listened to Dr. George Divoky speak about changes he has observed in a colony of Black Guillemots, a small northern seabird, which he has been monitoring since 1970. The changes to the Arctic over his career have been vast: the Arctic summer is now longer (number ice free days) and the ice cover on the Arctic Ocean has decreased, driven by increased temperatures. In other words: Climate Change. We often think of climate change as affecting animals at the population-level: range shifts over decades, or declines over generations. But George pointed out that changes are happening at the individual-level. He used Wisdom as an interesting example, pointing out that she has lived through vast changes to her environment since the 1950s. For example, during Wisdom’s life, CO2 concentrations in the atmosphere have increased to 340% over preindustrial (1700) levels (source). CO2 is recognized as one of the most abundant greenhouse gases directly contributing to increase in the global mean temperature. When you plot the data the pattern is striking. So George got me thinking: what other changes have occurred during Wisdom’s lifetime?

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Global mean carbon dioxide (CO2) concentrations measured in parts per million (ppm). Data compiled by the EPA from 10 different sources. (source)
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Global plastic production measured in millions of tonnes. (source)

Another key change that Wisdom has experienced is the accumulation of plastic debris in the ocean. When Wisdom hatched in the early 1950s, plastic was just becoming part of daily life. Since that time, global plastic production has increased rapidly, and ever since plastic entered the public domain, it has made its way to the ocean. Plastic’s durability, strength, and lightweight nature — the attributes that make it so appealing to us — also make it persist in the environment. In some parts of the world’s oceans, far removed from population centers along the coasts, there are 6 times more micro-plastics than plankton[1]. As a visual forager, Wisdom has had to learn the difference between this new man-made, potentially toxic substance and her usual food. Albatrosses are not particularly well suited for such decision-making, having to fight millions of years of evolution that point toward the mentality that “if it floats, it’s probably delicious”. Each year thousands of albatross chicks and adults die due to plastic ingestion.

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Laysan Albatross population nesting on Midway Atoll. The population has increased from an estimated "thousands of pairs" in the early 1900's to 450,000 pairs counted in 2016. (source and source)

While these two examples show a depressing situation that describes the disturbing impact that humans are having on our planet, not all changes that Wisdom has seen are negative. Midway was once a thriving and strategic military base with over 3,500 people living there during World War II. Before that, a vibrant and destructive demand for albatross eggs (for food), feathers (for women’s fashion) and guano (for fertilizer and explosives) depleted albatross populations across the North Pacific. As a result, albatross populations were smaller when Wisdom was born. Over Wisdom’s lifetime however, Albatrosses on Midway have recovered from a low of ~100,000 pairs in 1956 to ~450,000 pairs counted in 2016.

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Midway Atoll is home to more than 450,000 breeding pairs of Laysan Albatross.

While it is not all doom and gloom, earth is currently in a state of rapid change. Humans are reconfiguring and short-circuiting the processes that have shaped the planet that we know. The timeframe that we are setting is so much faster then past changes, that what the future holds is unknown. Wisdom has survived, and even thrived, in this environment of change, at least up to now. This gives me hope that the capacity to adapt is large in much of the natural world.

Art and Science: A Symbiotic Relationship

By Olivia Townsend

Today's post was provided by San Jose State student Olivia Townsend. Olivia is currently attending Moss Landing as an auxiliary student in MS 211: Ecology of Marine Mammals, Birds and Turtles. Lucky for us (!), she is also an amazing artist, and in keeping with our mission of interdisciplinary collaboration she has written this piece about scientific illustration and its role in supplementing traditional scientific observations.

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Art and science. Conventional thought places these two fields on opposite ends of the spectrum and some people still polarize them today. Science is data-driven and technical, while art is expressive and compelled by emotion. In fact, the process that happens in the laboratory is very similar to what happens in the studio. Both scientists and artists are investigators—they ask the big questions, scrutinize over detail, and strive to convey information and ideas. Moreover, art and science have a profound and historically rooted connection in which one undoubtedly cannot exist without the other.

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Beach Wrack: What is it and why is it here?

By Jarred Klosinski, Phycology Lab

If you’re like me and take long walks on the beach, you may have noticed more mounds of algae along the shore. These mounds are called beach wrack and can contain kelps as well as seagrasses. Other types of seaweeds including red and green algae are also found, but not as often.

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Kelp wrack composed of the giant kelp (Macrocystis pyrifera) and the feather boa kelp (Egregia menziesii) at an incoming tide near Monterey. Photo credit: Jarred Klosinski

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Sea otters participate in coastal restoration

by Jackie Lindsey, Vertebrate Ecology Lab

There's a new reason to love the world's smallest marine mammal species - so let's talk sea otters!

These voracious predators are again making headlines in the science world as a new paper comes hot off the (virtual) presses.  Hughes et al. (2013) published an article in PNAS entitled "Recovery of a top predator mediates negative eutrophic effects on seagrass".  This paper is truly a local collaboration, with scientists from UCSC's Long Marine Lab, the Elkhorn Slough reserve, USGS, CSU Monterey Bay, and MBARI.

The headline? Sea otters may have saved the Elkhorn Slough seagrass habitat by doing what they do so well: eating crabs.

Photo credit: Ron Eby http://www.vcstar.com/photos/2013/aug/26/307245/
Photo credit: Ron Eby http://www.vcstar.com/photos/2013/aug/26/307245/

To fully understand the premise of the paper, here's a little ecology review:

When we think about the health of a marine ecosystem, we often think of two major ways that the system could be controlled.

1) Top down:  A classic example of top down control is sea otters consuming urchins in a kelp forest.  These three trophic levels depend heavily on one another, so that if the sea otters in the kelp forest are removed by a predator (humans or killer whales) and can no longer keep the sea urchin population in check, the urchins will become overpopulated and consume so much of their prey (the kelp) that the kelp disappears, taking with it other creatures in the ecosystem that depend upon it.  If the sea otters are returned to the system, they consume enough sea urchins that the kelp is released from predation pressure, and the ecosystem can return to normal balanced levels.  Here's a figure by Estes et al. (1998) to illustrate this classic example.  Focus on the cartoons and the arrow sizes to track who eats what in each scenario.

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Figure 1 from Estes et al. 1998

2) Bottom up: Think of bottom up control like the workings of a traditional garden.  If you over-fertilize your tomato plants and they start to die off as a result, this bottom up forcing will impact the aphids that depend on the tomato plant for food, and in turn their ladybug predators.

Ladybugs consuming aphids on a tomato plant http://extension.umd.edu/growit/photos-aphids
Ladybugs consuming aphids on a tomato plant http://extension.umd.edu/growit/photos-aphids

Was that example not "marine" enough for you?  Let's get back to the sea otter news!

It is well known that Elkhorn Slough, an estuary located right next to MLML, is a nutrient-loaded system due to nearby agricultural activity.  In the past, biologists noticed that nutrient loading was having a negative impact on the estuarine reserve's seagrass beds, when algal epiphytes bloomed and overtook the seagrass.  (That's bottom up control!)  Hughes et al. showed that in the last 30 years, that trend of declining seagrass beds was reversed, even as agricultural runoff increased!

How??  Hughes et al. noticed that another thing happened about 30 years ago: southern sea otter populations recovered to the point that otters began colonizing Elkhorn Slough habitats.  Was this a coincidence?  The authors think that this is an example of an interaction between top down and bottom up control.

Figure 2a from Hughes et al 2013
Figure 2a from Hughes et al. 2013

Hughes et al. (2013) demonstrated that the interaction between sea otters and their prey species in Elkhorn slough created a 4-level trophic cascade that released the seagrass from top down control pressures, allowing it to flourish even in the presence of high nutrient loads.  In short, the sea otters ate the crabs, which in turn consumed less algal epiphyte grazers (snails, slugs), which in turn consumed more algal epiphytes (blanketing the seagrass), which allowed the seagrass to grow. This well-timed trophic cascade was lucky for the seagrass, and all other marine critters that depend on it for habitat in Elkhorn Slough.

The sea otters are helping to restore our coastline, and you can too!  Just five days until California's Coastal Cleanup Day, and it's not to late to volunteer!

My citations, in case you want to do a little more reading,:

Brent B. Hughes, Ron Eby, Eric Van Dyke, M. Tim Tinker, Corina I. Marks, Kenneth S. Johnson, and Kerstin Wasson (2013) Recovery of a top predator mediates negative eutrophic effects on seagrass. PNAS: 1302805110v1-201302805.

Estes JA, Tinker MT, Williams TM, Doak DF (1998) Killer whale predation on sea otters linking oceanic and nearshore ecosystems. Science 282(5388): 473-476

“Tails” from The Field

by Angela Szesciorka, Vertebrate Ecology Lab

Since May, the mammal lab has been as quiet as a post-apocalyptic library (yep, that quiet). For the marine mammologist (and birder), summer time is all about fieldwork — followed by lots and lots of data crunching and thesis writing. So with fall drawing ever closer (noooooo!), I wanted to check in with my labmates to see what they have been up to. Below is a quick summary from each of us. We’ll see you soon!

Ryan Carle: Ryan continued working on Año Nuevo Island, finishing data collection for his thesis on Rhinoceros Auklet diet and reproduction. He spends most of his waking hours on the Island identifying prey, restoring habitat, counting burrows, collecting boluses — you name it. When he’s not on Año, he’s trekking about California and making apple cider!

Casey Clark: Casey has been fervently writing up his thesis as he prepares to defend in the fall. Draft one? Check! Falling asleep on your keyboard? Check! He has also been helping out with seabird research in Astoria, Oregon. He did save time for fun too — camping, hiking, and kayaking. Jealous!

Marilyn Cruickshank: Marilyn spent the summer analyzing BeachCOMBERS data. She’s looking to see if the residence times of stranded birds on Monterey beaches can help with damage assessments and as a predictor of where most birds will wash ashore in future oil spills. Marilyn continued working for the stranding network and learned how to program in Matlab. She even found time to carve a new banjo. Nice wood-working skills, Marilyn!

Emily Golson: Emily has been doing nothing but data analyses. Her sea otter movement model has been developed and now she is fitting parameters of the model using otter re-sighting data. Oil spill forecasting data (from the DFW and NOAA) will allow Emily to run a simulation of sea otter movements to estimate the number of sea otters that could be oiled (using various severities, different surface current circulation patterns, and times of year). Stay tuned, because this fall Emily will be presenting posters at the Oiled Wildlife Care Network’s Annual Rehabilitation Conference (Oilapalooza) and the Society for Marine Mammology’s 20th Biennial Conference on the Biology of Marine Mammals. We can’t wait!

A resting sea otter. Photo by Nicole LaRoche.
A resting sea otter (Enhydra lutris). Photo by Nicole LaRoche.

Keith Hernandez: Keith started his sea lion diet study this summer. He’s been collecting scat off Año Nuevo Island with his collaborators and working with his summer intern, Ross Johnston, to process the scat; that is, removing and quantifying the hard parts and blending the remaining feces. Strong stomach, everyone, the poop room has returned!

Deasy Lontoh: As some of you may have read, Deasy traveled to Papua Barat, Indonesia (where she did her thesis data collection) to teach Indonesian school children about the threats that the endangered leatherback sea turtles face while nesting in Indonesia. Safe travels, Deasy!

Deasy with Indonesian school children. Photo from MLML.
Deasy with Indonesian school children. Photo from MLML.

Suzanne Manugian: Suzanne’s summer update: writing, writing, writing! She’s on chapter two of her thesis and expects her first draft to be done by September. She continues to monitor her seal haul-out sites, count seals for NPS, and will monitor marine mammals for the Bay Bridge project. A defense and marine mammal conference are looming in Suzanne's future. In her spare time, she’s been training for a few triathlons, a bike road race, and a half marathon... She also wrestles bears. Or so we hear. Kick-ass, Suzanne!

Melinda Nakagawa: Melinda is finishing up her thesis using remotely sensed oceanographic data to better characterize the California Current region (and the habitat of Sooty Shearwaters and their prey). Outside of that, her summer was spent chasing her little one around!

Gillian Rhett: Gillian is finishing up data collection and plans to graduate in the fall. She is using an epifluorescence microscope and scanning electron microscope to quantify and meiofauna (really small benthic invertebrates) from sediment cores that MBARI collected at whale fall sites in Monterey Bay. Gillian hopes to determine whether the meiofauna community is different under the whale bones versus the regular seafloor. Sooo cool, right?!?

Whale fall in Monterey Canyon from February 2002. Photo by MBARI.
Whale fall in Monterey Canyon from February 2002. Photo by MBARI.

Jacqueline Schwartzstein: This summer Jackie bade us farewell and moseyed up the Pacific Northwest to the evergreen state — Washington. Once there she kicked off her fieldwork, collecting gray whale prey data (benthic invert goodies, yum!) and got married. All in a days’ work. Congratulations, Jackie! Now get home because we miss you and your new hubby.

Angela Szesciorka: I started shipboard surveys in April. I’m basically a glorified ocean hitchhiker, riding vessels that are going between San Francisco and Los Angeles to survey for whales. Just me and the binos... well, and datasheets, food, and a helper, if I’m lucky. I’m hoping to do hotspot analysis with whale and ship distribution data to predict where ship-whale interactions might occur. Keith and I had an amazing journey on R/V Point Sur when we traveled from Oregon to Moss Landing in June. This August and September, I’ll be teaming up with John Calambokidis to tag humpback whales in the Traffic Separation Scheme off San Francisco. I hope to find out if humpback whale dive and foraging behavior is affected by the presence of large commercial vessels.

Surveying for humpback whales off California. Photos by Angela Szesciorka.
Surveying for humpback whales (Megaptera novaeangliae) off California. Photos by Angela Szesciorka.

Lisa Webb: Lisa spent her summer working on her thesis on the foraging ecology of Brandt’s Cormorants in Monterey Bay. A thesis defense is in her future. Stay tuned!

*Update from Lisa: Between trips to the beach with her almost two year old daughter, Lisa has been preparing to present her thesis results on Brandt’s Cormorant diet in the Monterey Bay area at an upcoming workshop, Predators and The California Current Preyscape. The focus of the workshop is to gather information pertinent to management of forage fishes in the changing California Current System. Presentations will span a wide spectrum (invertebrates, fishes, seabirds, and marine mammals) and will highlight short and long-term changes observed at the scale that predators forage and compete. The adequacy of ecosystem based management will be discussed at the end of the workshop. The Brandt’s Cormorant is endemic to the California Current, forages nearshore, and the central California population is increasing, yet only a few diet studies have been conducted in Monterey Bay. Lisa’s study indicates a major shift from rockfishes and squid in the 1970s to a coastal pelagic, northern anchovy, and sanddabs in the 2000s. Additionally, due to greater sampling frequency than previous diet studies, Lisa has documented short-term prey switching in Brandt’s Cormorants, exemplifying their ability to capitalize on a sudden influx of prey.*

Kristine Williams: Kristine is finishing up her thesis looking at the effects of different health conditions on hematology and serum chemistries in California sea lions. She worked with The Marine Mammal Center, collecting her data from their Sausalito facility while becoming a registered veterinary technician. Way to go, Kristine! She is currently working on final revisions of her thesis. Expect to see her defend in the fall!

A Visit to Año Nuevo Island

By Angela Szesciorka, Vertebrate Ecology Lab

In March the MS211 class (Ecology of Marine Turtles, Birds and Mammals) climbed onto a small inflatable boat, pointed offshore, and ran a half mile obstacle course through rocks, waves, and seals to Año Nuevo Island.

This tiny boat (named Dragon Rojo!) carried us to the island. About an eight-minute boat ride though, so not bad. Photo from Oikonos.org.
This tiny boat (named Dragon Rojo!) carried us to the island. About an eight-minute boat ride though, so not bad. Photo from Oikonos.org.

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Chronicles of a Curious Beachcomber

by Angela Szesciorka, Vertebrate Ecology Lab

A few Sundays ago — Super Bowl Sunday, in fact — I took a three-hour walk along the beach at Fort Ord in Monterey, CA with Don Glasco, a systems engineer and former cartographer.

This wasn’t a leisurely pursuit, but my volunteer service to the Sanctuary Integrated Monitoring Network’s (SIMoN) Coastal Ocean Mammal and Bird Education and Research Surveys, also known as Beach COMBERS.

I meet Don at Fort Ord Dunes State Park in Marina around 9 a.m. After downing the last of my coffee, we head out into the foggy morning.

Don Glasco referring to the almighty bird book to identify an unknown species by its toes. Photo by Angela Szesciorka.
Don Glasco referring to the almighty bird book to identify an unknown species by its toes.

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Dem bones, dem dry bones

by Jackie Schwartzstein, Vertebrate Ecology Lab

Most of us remember the song from childhood:

'Toe bone connected to the foot bone, Foot bone connected to the leg bone, Leg bone connected to the knee bone…'

But here at MLML the students in the Marine Birds and Mammals class (MS 112) are quickly finding that what we learned as kids just doesn’t seem to apply anymore! The skeletons of birds, marine mammals, and turtles are MUCH more complicated than the sweet little bones ditty implies. Have the animals changed since I was in fourth grade?! What exactly IS the ‘foot bone’, anyway?!

Rear limbs of the California Sea Lion.
Photo by Jackie Schwartzstein
Can you find the foot bone?

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The Early Bird Gets the Fish in this Case (and a Great Tide-Pooling Experience)

By Catherine Drake, Invertebrate Zoology Lab

In early June, I went camping with my family in Southern California at El Moro Campground, a part of Crystal Cove State Park. While there one day, I was excited to learn that there was going to be a -1.8 foot tide at 6 am. So, the next morning, my mom and I woke up bright and early and made our way to Corona del Mar Beach.

Corona del Mar Beach at a -1.8 foot tide early one June morning. Photo by Catherine Drake.

The last time I visited Corona del Mar Beach, which is a relatively unknown tide-pooling location, was about two years ago. I noticed that in this two-year span, this particular rocky intertidal ecosystem changed drastically: the mussel beds expanded, less surfgrass canopied the habitat, and both crustose coralline and red algae filled the void. Ochre sea stars, once abundant on the northern part of the beach, are now flourishing about 100 yards south for better access to the mussel beds.

A flourishing mussel bed (Mytilus sp.) in the rocky intertidal.  Photo by Catherine Drake.
A shore crab (Pachygrapsus sp.) eats a limpet as it moves through the intertidal. Photo by Catherine Drake.
A uniquely neon green anemone (Anthopleura sp.). Photo by Catherine Drake.

This was by far my favorite tide-pooling experience. I spotted organisms I had never seen in the rocky intertidal before, such as a Hopkin's rose nudibranch (Okenia rosacea). I also was witness to feeding behaviors I had not previously seen, such as a crab eating a limpet as it traversed the rocks, and an egret moving within a tide pool with such delicacy to find its prey, an oblivious fish.

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An egret prevails in its hunt for breakfast. Photo by Catherine Drake.