Category: marine and aquatic life

Readers’ wildlife photos

August 25, 2025 • 8:15 am

Today, mathematician and Hero of Intellectual Freedom, UC Davis’s Abby Thompson has more lovely intertidal pictures from California. Her captions and IDs are indented, and you can enlarge the photos by clicking on them.

The Northern California tidepools are filling with kelp, and creatures are hiding away under it.   Here are some photos while there’s still a bit of summer left.     These are from July, except for the pelicans (August 1). Thanks as usual to experts on inaturalist for some of the IDs.

Tegula funebralis (black tegula): I love these tracks on the sand at low tide; it looks as though the snails are trying to tell us something:

Closeup of the barnacle-encrusted snail from the first photo:

Hesperocyparis macrocarpa (Monterey Cypress). The trunks get stroked by many hands as people pass them on their way down to the beach:

Pelecanus occidentalis (brown pelican): There must have been a large shoal of fish near shore; the pelicans (it seemed like hundreds of them) were going nuts.    Their lethal dives, with those incredible beaks, makes their relation to dinosaurs look very convincing.  The Point Reyes peninsula is in the background:

Family Ammotheidae (Pycnogonid-sea spider): The lumpy white spots on the legs are eggs (what a place to carry them!), which I believe makes this a female.  The males carry the eggs after they are fertilized:

Tenellia lagunae (nudibranch):

The next few photos are through a microscope.  I have an ancient Leitz Wetzlar dissecting scope, with an old iphone precariously clamped over one eyepiece. There must be a better way, but I haven’t figured it out yet.

Diatoms: Genus Isthmia; Lou Jost’s beautiful post on WEIT on the Challenger Expedition and the diatoms they found  was inspiring. It’s disconcerting, as a non-biologist, to look through a microscope at a fluffy, frothy bit of seaweed (the reddish stuff) and see, scattered all through it, these incredibly regular geometric shapes:

Diatoms closeup:

Neosabellaria cementarium ((tiny) polychaete worm):

Phylum Foraminifera: This was a surprise to me, partly because I had never heard of foraminifera, but mostly because it turns out they’re single-celled organisms (like diatoms), so that’s one cell you’re seeing.   Google AI says this about the difference between diatoms and foraminifera: “Diatoms are photosynthetic algae with silica cell walls, while foraminifera are amoeboid protists with calcium carbonate or agglutinated shells.”

There are many more elaborate/complex ones than this one (there’s one that looks a lot like a loaf of challah, for example).   It’s worth googling “foraminifera” and “Ernst Haeckel” to see some amazing illustrations. The Challenger Expedition discussed by Lou Jost also collected and documented foraminifera.  According to Wikipedia, the first picture of one was by “…Robert Hooke in his 1665 book Micrographia”.  This book (available through WikiSource online) has charming sections like: “Of the Teeth of a Snail”, and “Of blue Mould, and of the first Principles of Vegetation arising from Putrefaction”.   The possible foraminifera appears as figure X in Schema 5.   He says (in Observation XI) “I view’d it every way with a better Microscope and found it on both sides, and edge-ways, to resemble the Shell of a small Water-Snail with a flat spiral Shell:” Imagine being one of the first to be able to peer into this world!

The camera for the first six pictures in an Olympus TG-7.

Readers’ wildlife photos

July 6, 2025 • 8:15 am

If all goes well, these photos from John Avise, one showing pinnipeds, will appear as his usual Sunday contribution. (I’m scheduling it in advance.) John’s captions and IDs are indented, and you can enlarge the photos by clicking on them.

Whale-watching Trips, Part 4. Pinnipeds

No, they’re not cetaceans, but seals and sea lions are other marine mammals sometimes seen on whale-watching tours out of Southern California.  This week I continue the “Whale-watching” series by showing my photos of some pinniped species that I’ve encountered on these nature excursions.

California Sea Lion (Zalophus californianus):

California Sea Lion, juvenile:

California Sea Lion, head shot:

California Sea Lion, group basking:

Harbor Seal (Phoca vitulina), swimming:

Harbor Seal, basking:

Harbor Seal, headshot:

Harbor Seal, pup nursing:

Harbor Seals, basking:

Harbor Seals, swimming and basking:

Harbor Seals, adult and pup on land:

 

Readers’ wildlife photos

June 29, 2025 • 8:15 am

Today is Sunday, and that means it’s John Avise Photo Day.  Today John sends us pictures of dolphins. His captions and IDs are indented, and you can enlarge the photos by clicking on them.

Whale-watching Trips, Part 3. Dolphins

This week I continue the Southern California “Whale-watching” series by showing my photos of some smaller cetacean species that are often seen on these three-hour off-shore nature excursions.

Common Bottlenose Dolphin, Tursiops truncatus:

Bottlenose Dolphin jumping:

Bottlenose Dolphin, adult and calf jumping:

Bottlenose Dolphin, blowhole close-up:

Bottlenose Dolphin fluke:

Risso’s Dolphin, Grampus griseus:

Risso’s Dolphin, dorsal fin:

Risso’s Dolphin, blowhole and spout:

Common Dolphin, Delphinus delphis, pod:

Readers’ wildlife photos

June 28, 2025 • 8:30 am

I’m running very low on readers’ wildlife photos, so send some in this week if you got ’em. They may have to wait a while to be posted, but I don’t like to run out. Thanks!

Today’s batch of marine pictures comes from mathematician and intellectual hero Abby Thompson, who loves to photograph  tidepools of California. Her captions and IDs are indented, and you can enlarge the photos by clicking on them. There are some very weird worms here; see especially the last two.

The number of different species of marine worms is incredible, with many of them undescribed.   As one of the experts who is kind enough to help with IDs on inat has said, “so many worms, so little time”.     A remarkable recent paper, started by a student project at the Bodega Bay Marine Lab, documents 11 new species of nemertean worms found in a very small area that has been studied extensively for decades.  So what follows is just a sampling of some of the species found on a short stretch of the Northern California coast.

Pterocirrus montereyensis:

Paradialychone ecaudata:

Genus Thelepus; this medusa-like creature is in the family Terebellidae, called “spaghetti worms” for obvious reasons:

Genus Naineris. It’s hard to pick my favorite among all these worms, but this is a strong contender. The species here is unclear and possibly undescribed. I’ve found just a few of these, in 3-4 very small (like 6”x8”) always-shaded pools in the high intertidal zone.    They appear (as does so much) as a slight pinkish fuzz until they are magnified. There’s a video of one eating here,  The worm transports sand grains to its mouth along those dark channels, then apparently scrapes off the organic material:

This is a worm trifecta from the same tiny pool- Genus Naineris, Paradialychone ecaudata, and a peanut worm, Phascolosoma agassizii– that’s the black-and-white splotchy one:

Genus Aphrodita (sea mouse). From Wikipedia:  “The name of the genus is taken from Aphrodite, the ancient Greek goddess of love, said to be because of a resemblance to human female genitalia.” I think “sea mouse” is a better descriptor, myself.  Its camouflage on the sand is almost perfect.  I included the next picture of its underside so you can actually see it:

Aphrodita, the underside:

Family Phyllodocidae (paddle worm) This tiny guy (about ½”) looked like a miniature dragon:

Serpula columbiana; luckily, these lovely worms are fairly common:

Serpula columbiana (the pink-and-white bit) closing up:

Genus Amblyosyllis; this and the next one are the other contenders for my favorite. They look to me like illustrations from Dr. Seuss.  They’re both undescribed species.  These two are the only ones of this genus I’ve found:

Genus Amblyosyllis:

Readers’ wildlife photographs

June 2, 2025 • 8:15 am

Math professor and Hero of Intellectual Freedom Abby Thompson of UC Davis has sent us some tidepool photos, along with a few birds. Her captions are indented, and you can enlarge the photos by clicking on them.

The first picture is of a pair of foolish birds from my back porch, followed by some Northern California tidepool pictures from late April and May.   The tides the last week of May were among the lowest of the year, occurring at a very unfortunate time of day (near dawn) for those who prefer a leisurely morning, like me.    As usual I got help from people on inaturalist for some of the IDs.

I don’t understand how mourning doves ever manage to reproduce. Here’s a pair pondering building a nest on the extremely wobbly fan hanging from the trellis over our porch. I’ve also seen them trying to nest on the peak of the roof and on a very narrow garden railing.  They give new meaning to the word birdbrain.    I strung up a nice, spacious, secure basket for them right near the fan, which they totally ignored.   They eventually gave up on the fan; they’ve probably found a nice spot smack in the middle of a parking lot somewhere.

On to the tidepools:

Thorlaksonius subcarinatus: This is a species of amphipod, which (I feel like I keep saying this) is tiny, just a bright orange speck. Amphipods are like isopods (the roly-polys in your garden) except they’re flattened vertically instead of horizontally.  The Thorlaksonius part is for sure, the species seems likely correct:

Liparis florae (tidepool snailfish).  About 2” long.  The second picture is a close-up of its weird eye:

Rostanga pulchra (nudibranch). This species eats a bright orange sponge, on which it becomes practically invisible:

(Family) Sabellidae (feather duster worm) It’s not possible even to determine genus from this photo:

Phidiana hiltoni (nudibranch):

I took a picture of the brown-and-white-striped worm (Tubulanus sexlineatus) and only noticed afterward that the photo includes both a nudibranch (Coryphella trilineata) to the right of the worm and a sea spider (Pycnogonum stearnsi) to the left. Tidepools are crowded places:

A little jellyfish, Polyorchis haplus (I think). This one was stranded on the sand, but when plopped into a small pool it started zipping around. The red spots are eyespots:

Acanthodoris nanaimoensis (nudibranch). I don’t see this species very often, and it’s a knock-out:

 

Camera info:  Mostly Olympus TG-7 in microscope mode, pictures taken from above the water.

Readers’ wildlife photos

May 3, 2025 • 8:15 am

Our stalwart readers have come through with several batches of photos, so we’re good to go for about a week.

Today’s contribution comes from UC Davis math professor Abby Thompson, also a Hero of Intellectual Freedom. Abby’s captions and IDs are indented, and you can enlarge her photos by clicking on them.

In Northern California, April blew in the way March is supposed to, like a lion, with gusting winds and high surf.

The first set of creatures below have a lovely common name: by-the-wind sailors, and a mellifluous scientific name: Velella velella.   Each mini-sailboat is actually a colony of hydroids.     They’re blown willy-nilly across the surface of the sea, and when the winds and tides hit just right, they wash up onshore in incredible numbers.  The first picture is the beach so covered with them it looked like it had snowed.  The second is a closer-up picture of a cluster of them.  The third and fourth show first a single “boat” floating right-side up, with the sail sticking up perpendicular to the surface, and then a few upside down, showing the tentacles which usually hang underneath.  Velella velella are related to Portuguese men o’ war, but their tentacles don’t sting (much- at least not for humans).

Both Velella velella and Portuguese men o’ war have nudibranch predators, including Fiona pinnata and Glaucus atlanticus (blue dragon).  The spectacular blue dragon seems to be always blue, and Fiona pinnata can take on the beautiful blue of its prey. Glaucus atlanticus  concentrates the (painful) venom of the Portuguese man o’ war  and reportedly is excruciatingly painful to the touch.  Luckily the two really venomous species need warmer water than we have in Northern California.

Velella velella (by-the-wind sailor):

Epiactis prolifera (brooding anemone) This species broods its young on the outside of its column. The babies are the cream-colored flower-like things:

Epiactis prolifera again- in this one, the kids seem to have taken over the place, as kids are wont to do:

Nucella ostrina (Striped dogwinkle). These usually have boring grey and white strips, but every once in a while they’re this spectacular orange. Also I like the name “dogwinkle”:

Doto amyra (nudibranch):

Paradialychone ecaudata (another species of feather duster worm). These just appear as a fuzz on the bottom of the pools, until you look at them with some magnification:

Camera info:  Mostly Olympus TG-7 in microscope mode, pictures taken from above the water.

Readers’ wildlife photos

April 8, 2025 • 8:30 am

Today we have a lovely batch of tidepool organisms taken by UC Davis math professor Abby Thompson, who is also a Hero of Intellectual Freedom.  Abby’s captions and IDs are indented, and you can enlarge her photos by clicking on them.

More tidepool pictures from Dillon Beach, CA.   The best tidepooling season is just getting underway.  There are some big tides at the end of April, and they’ll recur through July, with the low tides at ghastly hours of the morning.    These pictures from March were from less painful times of day.   There are a few species I’ve posted before, but they had some especially photogenic representatives this month.

Several of these animals are really (really) tiny, and some are both tiny and fast, so some of the pictures aren’t perfect, but I think they’re interesting creatures.

Phidiana hiltoni (nudibranch).   Posted before, but this one was a beauty:

Genus Ophiopholis (brittle star). Distinguishing species in this genus requires better pictures than this one.  This tiny- about an inch tip to tip- brittle star was on the underside of a rock.    These move fast and gracefully.    They’re in the same phylum as big ochre stars, the sea urchins (see the next two pictures) and sea cucumbers:

Strongylocentrotus purpuratus (purple sea urchin). I know, it’s green, but the juveniles start green and then turn purple.    The next picture shows its mouth on the underside:

Sea urchin mouth:

Family Sabellidae (feather duster worm). Another very tiny creature, visible to the naked eye as just a slight pink fuzz.   This marine worm lives in a tube of its own creation,  and retracts into the tube in a flash if disturbed.  The dark dots at the base of the “feathers” are eyes:

Caesia fossata (eggs from this snail).

Margarites pupillus (tentative ID) I liked the bit of opalescence on the shell:


Coryphella trilineata (nudibranch). Another one I’ve posted before, posing for the camera:

Genus Gnathopleustes (amphipod). Yet another tiny guy.    I’ve found just a few of these, a speck of bright color in the seaweed:

Mopalia acuta (chiton).   The Mopalia species can be hard to distinguish from photos, so this ID should be taken with a grain of salt.    Chitons usually cling to a rock like a limpet, but they can curl into a ball like a roly-poly to protect their vulnerable body if they get dislodged:

Camera info:  Mostly Olympus TG-7, in microscope mode, pictures taken from above the water.