Yesterday afternoon when I got home I checked out the red-tailed hawk nest across the canyon and didn't see anybody home. Then I started scanning the trees on both sides of the canyon to see if the parents were around. While I was looking the dad flew in with prey and perched on the top of one of the trees. But he didn't start eating right away so I thought he might have been showing the prey to the kids. Sure enough, we found one of the juveniles perched just a short distance away.
The adult male's plumage is nice and sleek, and he perches quite easily on a branch that sways dramatically in the afternoon wind. The juvenile's feathers are rumpled and its head looks small, probably because it hasn't been feathered very long, and it had some problems with balance.
At some point the juvenile managed to hop over to its dad, who then shared some of his food.
So we knew for a fact that at least one of the juveniles had fledged; however, we didn't find the other juvenile anywhere. We did see the adult female perched atop a tall snag on our side of the canyon; she was looking around but didn't seem worried so we figured that the second juvenile at least wasn't on the ground or in some other danger.
And lo and behold, as the sun was beginning to set and light the other side of the canyon, we found both juveniles and the adult female perched on trees across the way. So both of the kids had fledged successfully!
I don't know what the juvenile on the left is doing and why it appears not to have a head. We still haven't actually seen either of the juveniles flying, but by the time it was getting dark both had returned to the nest for the night. I imagine they slept well after all the day's exertions!
Our red-tailed hawk chicks are sooo close to fledging now! I've been told that the tree-nesting raptors usually first leave the nest to hop around on branches; hence they're called "branchers." This afternoon I watched the chicks and was able to catch some of the maneuvering, which included hopping around the edge of the nest.
One of the chicks seems more adventurous than the other. I know that female raptors are larger than males, so I think that males reach their fledging size sooner than their sisters. Which would mean that this earnest almost-brancher is a boy. He'll be flying soon!
This morning I took a small group of Seymour Center volunteers on a tidepooling trip to Point Piños (see red arrow in the photo below). Point Piños is a very interesting site. It marks the boundary between Monterey Bay to the right (east) of the point and the mighty Pacific Ocean to the left (west).
As is my usual habit, we began our exploration on the Pacific side of the point. Almost immediately, Victoria found an octopus! And a couple of meters away, she found another one!
As we approach the summer solstice, the algae and seagrasses are at their most lush. Point Piños is a fantastic site for algal diversity; every time I come here I want to take some back with me so I can study it at the lab. Alas, collecting at Point Piños is not allowed even for someone (like me) who holds a valid scientific collecting permit.
And yes, that log-like object towards the upper-left corner is a harbor seal (Phoca vitulina). A handful of seals were hauled out on the rocks.
However, I was much more interested in the invertebrates. I wasn't looking for anything specific, but in the back of my mind I was keeping track of certain nudibranchs and looking for small stars.
We did see many Patiria miniata (bat stars) in the 1-2 cm size range. Most of them were a bright orange-red color, but some were beige, yellow, or blotchy. There was one large (bigger than my outstretched hand) Pisaster ochraceus that was intensely orange. And Point Piños is always a good spot to see many of the six-armed stars in the genus Leptasterias.
In terms of nudibranchs there were many Doriopsilla albopunctata, a yellow dorid with tiny white spots. We saw quite a few of them crawling around on the emersed surf grass, as well as in pools. And of course Okenia rosacea (Hopkins' rose) was there, although not in the huge numbers I was expecting.
In the low zone I saw a few thalli of the intertidal form of Macrocystis pyrifera, the giant kelp that forms the forests that the California coast is famous for. I'd seen this intertidal form named Macrocystis integrifolia, but it appears that now the two forms (intertidal and subtidal) are both considered to be M. pyrifera. To my eye, the intertidal form differs morphologically by having rounder pneumatocysts (floats) and a holdfast that is less dense than the subtidal form.
Hermit crabs are diverse and abundant at Point Piños. Here's an example of Pagurus samuelis, the blue-banded hermit crab; even when you can't see the blue bands on the legs, the bright red antennae are a major clue to this crab's identity.
When we climbed over the point to the Monterey Bay side, I found two of these little gastropod molluscs, which I didn't recognize. They are about 1 cm long, with a brown lumpy mantle that can covers the shell, which is pinkish in color. After putting it out on Facebook that I needed help with the ID, a bunch of friends and friends of friends chimed in (thanks John, Rebecca, Barry, and David!) and I was able to determine that these little guys are Hespererato vitellina:
On our way back up the beach we noticed long windrows of Velella velella, the by-the-wind sailors, washed up. While most of them were faded and desiccated, there were enough freshly dead ones that were still blue, which may have washed up on the previous high tide.
All in all, a very satisfactory morning. I saw things I expected to see, some things I didn't quite expect but wasn't surprised to see, and some things I'd never seen before. That Hespererato vitellina was completely new to me, which is always exciting.
Next up: What kinds of things live in white calcareous tubes?
See how it's covered in water? I took this picture at about 13:00, probably right at high tide. And of course when I was out there this morning at 06:00, it was low tide. It wasn't the greatest of low tides but it allowed me to see what I needed to see and have a front-row seat watching the early morning surfers going up and down on the big swell that's blowing in.
Obviously, visits to the intertidal need to be timed with the tide cycle. At this time of the year we get our lowest spring tides in the morning every two weeks or so, which is great for me because I am a creature of the morning. I can get up hours before the sun rises, but don't ask me to do anything that requires any intense brain activity after about 21:30.
Low tide this morning was at 05:29, when it was still almost full dark. There was plenty of light to see by the time I got out to the rocks. The tide wasn't very low and the swell was big, a combination that makes for some pretty spectacular wave watching. Here's a view towards the marine lab from my intertidal bench; look at all that frothy water!
So the water was big and the tide was mediocre, but it was still a glorious morning. Where I was the bench looked like this:
What a difference seven hours can make! See that tiny black dot in the ocean? That's a surfer. While I was out there none of the three surfers I was watching did any actual surfing.
I can't seem to stop taking pictures of anemones:
My prize of the day appeared as I was walking back. I happened to look down at the right time and saw this little guy:
I was able to watch the octopus for a couple of minutes. Its mantle was about 3 cm tall, and I'd guess that all spread out the animal was perhaps a bit larger than the palm of my hand. When I got up to move around to the other side of the pool for a different camera angle, the octopus oozed underneath the mussels and just disappeared.
Before it vanished I was able to catch it in the act of breathing.
Although it looks like a head, given the position of the animal's eyes, the part of the animal that's pulsating is the mantle. The visceral mass and gills are contained in the space enclosed by the mantle; not surprisingly, this space is called the mantle cavity. The octopus flushes water in and out of the mantle cavity to irrigate its gills. When it wants to swim it closes off the opening to the mantle and forces water out through a funnel which can be rotated 360° so it can jet off in any direction. But this time the octopus didn't use jet propulsion. It just oozed away.
Our red-tailed hawk chicks are growing bigger every day, and trading fluff for feathers as well. Their bodies are almost completely feathered by now, which makes their heads look small and strange, as though the heads are developing more slowly than the rest of the body. Given that the head is where the brain is located, maybe it actually is growing at a different rate from the body.
For quite long stretches of time now, both parents are away from the nest. Usually the chicks are just lazing around, napping below the level of the nest rim so that we can't see them. But occasionally they stand up and look around. Already they've got that "eyes like a hawk" thing going, and they'll stare back at us through the spotting scope. And we can tell when the parents are approaching with food before we can see them, because the chicks make a holy hell of a racket. From what I've observed, they've been eating a lot of rodents lately. Good hawks! Eat all the gophers!
Sometimes the chicks get up and stretch. They need to build strength in their growing flight muscles, so they stretch up and flap their wings a bit. They're pretty long-legged and gangly now. They look sort of like bald eagles, but that's only because they don't have feathers on their heads yet.
Having never kept close eyes on baby red-tailed hawks before, I can't guess how long it'll be until these chicks fledge. My experience watching peregrine falcons fledge at the marine lab tells me that, for those raptors at least, fledging doesn't occur until the head is more completely feathered. If that also holds for red-taileds, then these guys have a bit of feather-growing to do. Besides, the more time they spend stretching and flapping, the better shape their muscles will be in for when they take that eventual first journey into the air.
I've been told what to expect when these guys get close to fledging, and what to do if one of them ends up on the ground. I'll keep you posted!
When I was in graduate school I found myself drawn to the "old-fashioned" skills of classical zoology: observation of and experiments with living animals. I had, and still have, very little interest in the new-fangled high-tech methods of studying animals, and part of me strongly resents having to homogenize an animal to know what its name is. I leave that sort of biology to the systematists because, after all, the animal doesn't care what name we give it, and the names themselves are merely a way for us humans to communicate amongst ourselves (although in the best of all possible worlds the taxonomy reflects the evolutionary history of the group in question, which is itself a Very Useful Thing). I am much more interested in what the animal actually does as it goes about living its life.
A priest I know has said repeatedly that observation is a passive activity, and I've told him that he wouldn't think so if he actually knew how to do it properly. Careful observation takes a tremendous amount of mental focus, and like all other skills gets easier the more one does it. But I fervently disagree that observation is at all passive. If it is, then you're not doing it right. There are tricks of the trade that facilitate observation, of course, such as sketching and annotation, and I have all of my students do at least some drawing. My upper-division students keep a lab notebook that consists of drawings and notes that document their lab activities during the semester. Sometimes they grumble about having to draw and most of them worry about their self-perceived lack of artistic skill, but they do come around and realize that drawing forces them to really pay attention to what they observe. And no, I do not allow them to substitute photographs for drawings.
In graduate school I was fortunate enough to fall under the tutelage of one Todd Newberry, who directly and indirectly shaped how I think about animals and biology. He also taught me a specific type of scientific illustration, which he himself had learned from a pair of biologists in Paris. I used these techniques to draw the life history stages of my dissertation study organism, the moon jelly Aurelia sp. My favorite of this group of drawings is the juvenile medusa, or ephyra:
Several years ago now, I put together a handout of sea star larval development for my invertebrate zoology students. These pen-and-ink drawings were done using the same techniques, but I left out the stippling as the larval anatomy became more complex. Part of the beauty of drawing as a means of documenting my observations is that I can select what to include which obviously reflects what I feel is important. Sometimes the decision about what to omit helps me focus on the structures that really matter, which of course depends on the purpose for any particular drawing.
So there are some of my drawings. One of my goals for the summer is to put together a suite of similar drawings of my sea urchin larvae, to complement the sea star set. It will give me an excuse to clean out my technical pens--they've been sadly neglected for years, and I hope they can be revived--and spend time with my photographs. I also have plans for some pencil drawings on black paper. I'm looking forward to tapping into the artistic side of my brain again for a while!
As a native Californian, I've been living with drought my entire life. Well, maybe not so much during the El Niño of 1997-98, but even then the thought "We have water now but might not later..." was always in the back of my mind. This season we had a great few weeks of rain in late November and early December, then January was bone dry and February has been disappointing as well.
This weekend an Arctic storm is moving through the region, bringing rain and cool temperatures to coastal areas and (hopefully) snow in the Sierra Nevada. Here in Santa Cruz it hasn't rained much yet but we did get a few decent showers this morning. It just so happened that I headed down to the marine lab between showers, and the light was magnificent. The water was that magical color of aquamarine and seaglass green that I associate with the tropics. The sun was shining, casting cloud shadows on the water, which added depth to the color palette when combined with the kelp bed. So pretty!
Brown pelicans (Pelicanus occidentalis) were one of many bird species whose populations were devastated by widespread use of the pesticide DDT in the mid-20th century; in 1970 it was listed on the federal Endangered Species List. After the general use of DDT was banned in the United States in 1972 the population began to recover, and in 2009 the brown pelican was removed from the Endangered Species List (I believe the bureaucratic jargon for that is "de-listed"). It is now not unusual to see long lines of pelicans skimming the waves as they fly just above the ocean surface.
Today I didn't see any large groups of pelicans in flight, but I did catch this one flying by right in front of me.
Anyone who knows me personally knows that I'm not a big cheerleader for the marine mammals. However, seeing cetaceans in the wild is always a treat. This morning I was lucky enough to catch this pod of dolphin-type critters as they swam right off the point. There were 6-8 of them, I think. As they swam past the marine lab a couple of them indulged in some tail slapping.
I'm not enough of a cetacean expert to be able to identify the animals from photos. They did have dolphin-like dorsal fins but I couldn't see a prominent rostrum on any of them. I didn't have my binoculars with me . . . and I call myself a naturalist??
Since the animals were not traveling very quickly I decided to see if I could catch them on video. I was lucky enough to get this clip:
Can anybody help me identify what these animals are?