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Author: Allison J. Gong

Early morning low tides are the best

Posted on 2015-06-052023-01-06 by Allison J. Gong

This morning I went on a solo trip to one of my favorite intertidal sites up the coast a bit. I’ve been busy with stuff at the marine lab and my house is a construction zone this summer so it was really nice being alone in nature for a couple of hours before most people had gotten out of bed.

I didn’t find what I was looking for but did see some great stuff that I wasn’t looking for, which is just as rewarding.

The approach to the beach over the dunes is always spectacular even on a gloomy morning. I find this color palette very soothing.

The hike over the dunes, 5 June 2015. © Allison J. Gong
The hike over the dunes
5 June 2015
© Allison J. Gong

The site itself is rocky with a sandy bottom. Depending on the severity of recent storm action there can be more or less sand. Winter storms wash sand away, while in the summer the sand tends to accumulate and can bury the rocks to surprising depths.

Surfgrass bed (Phyllospadix sp.) and rocks at Franklin Point, 5 June 2015. © Allison J. Gong
Surfgrass bed (Phyllospadix sp.) and rocks at Franklin Point
5 June 2015
© Allison J. Gong

It may be an optical illusion, but when I’m scrunched down in amongst the rocks it appears that the waves are breaking at heights quite a bit above my head. Most of the water’s force is dissipated as the waves wash over the rocks, and unless I’ve wandered out too far, by the time it gets to me all I need to worry about is whether the surge will overtop my boots. Which has indeed happened and makes for a cold squelchy morning.


And now for some happy snaps!

A small mid-intertidal pool at Franklin Point, 5 June 2015. © Allison J. Gong
An example of intertidal biodiversity at Franklin Point. The most conspicuous organisms are Ulva (sea lettuce), coralline algae (the pink stuff), small acorn barnacles, the tube-dwelling worm Phragmatopoma californica, and small anemones in the genus Anthopleura
5 June 2015
© Allison J. Gong
I love my hip boots!  © Allison J. Gong
I love my hip boots!
© Allison J. Gong
Pagurus hirsutiusculus hermit crab in shell of the snail Olivella biplicata, 5 June 2015. © Allison J. Gong
Pagurus hirsutiusculus hermit crab in shell of the snail Olivella biplicata
5 June 2015
© Allison J. Gong
A beautifully camouflaged kelp crab (Pugettia producta) hiding in plain sight, 5 June 2015. © Allison J. Gong
A beautifully camouflaged kelp crab (Pugettia producta) hiding in plain sight
5 June 2015
© Allison J. Gong

Because, really, doesn’t everybody have a favorite red alga? This is mine. It presses gorgeously and is so damn beautiful!

Erythrophyllum delesserioides, 5 June 2015. © Allison J. Gong
Erythrophyllum delesserioides
5 June 2015
© Allison J. Gong

At one point I saw a worm-like thing thrashing around in a shallow pool. Turns out it was a polychaete worm, probably in the genus Nereis, doing epic battle with a predatory nemertean worm (Paranemertes peregrina). By the time I figured out what was going on and stuck my camera in the water the interaction had more of less come to an end. The polychaete did get away without apparent damage, but it was moving pretty slowly afterward. In this video Nereis is the segmented worm that’s doing all the wiggling, and Paranemertes is the purple and beige unsegmented worm that you can sort of make out in the top of the frame. I wish I had been swifter on the uptake with the camera.


And the pièce de résistance for this trip:  A little sea hare! This guy was so small (about 2.5 cm long) that at first I thought it was a clump of red algae. Then I saw the little rhinophores (those ear-like projections that give them their common name) and recognized it as a sea hare. Amazingly cute!

A little sea hare (Aplysia sp.), 5 June 2015. © Allison J. Gong
A little sea hare (Aplysia sp.)
5 June 2015
© Allison J. Gong

I was lucky enough to capture some video of this critter crawling around.

Aside from the rhinophores it doesn’t look hare-like at all, does it? I wonder about common names sometimes.

All in all, it was a great morning. An early morning low tide is the best reason I can think of to crawl out of bed at 04:30!

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A glass half full

Posted on 2015-06-042023-01-06 by Allison J. Gong

It’s becoming quite clear that I don’t have to worry about having too many sea star larvae to deal with. While the embryos from my F1 x M1 (Purple x Purple) cross had hatched this morning, nothing from the F2 x M1 (Orange x Purple) cross looked promising. I’m about ready to write off these guys and dump them all down the drain, but will give them until tomorrow to pull themselves together and do something that doesn’t look all wonky.

In the meantime, it’s really fun looking at the good embryos from the F1 x M1 mating. They hatched out of their fertilization envelopes and have become elongated, sort of like stubby Tylenol caplets. This elongation defines a functional anterior-posterior axis, and the animal swims with its anterior end forward.

Gastrulating embryo of Pisaster ochraceus, 4 June 2015. © Allison J. Gong
Gastrulating embryo of Pisaster ochraceus
4 June 2015
© Allison J. Gong

Gastrulation is the process of forming the first larval gut, or archenteron. Remember how yesterday the embryo was a hollow ball of cells called a blastula? In these echinoderms gastrulation is simply an invagination into the blastula. Imagine poking your finger into an inflated balloon:  The balloon is the blastula and your finger forms an invagination, or channel, through it. In embryos, gastrulation begins at a site on the blastula called the blastopore; this is where you’d stick your finger into the balloon in our analogy.

Most animal guts have two openings, a mouth and an anus. You understand what happens at each of those openings. The archenteron is a gut, one of whose openings is the blastopore. The fate of said blastopore is to be either the mouth end or the anus end of the archenteron. In echinoderms, the major invertebrate phylum that makes up a larger grouping of animals called the deuterostomes, the blastopore becomes the anus, with the mouth breaking through as the process of gastrulation finishes. And lest you think that possessing an anus before a mouth is somehow less evolved than the reverse would be, you might be interested in knowing that we humans are also deuterostomes. That’s right, each of you reading this blog, as well as the one who writes it, built an anus first and a mouth second.

These sea star embryos swim really fast! I had to squash them under a cover slip to snap some halfway decent pictures, and even then it wasn’t easy to slow them down or chase them around on the slide. You can get a feel for how fast they can move in this short video clip:

The archenteron appears to wobble because it doesn’t go straight through from the blastopore to the apex of the embryo. The mouth will break through along one of the sides, resulting in a curved gut. I suspect that when I look at the embryos tomorrow they will have graduated to the status of larvae, with complete guts. Then I get to start feeding them and watching them grow.

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Questions and answers

Posted on 2015-06-04 by Allison J. Gong

I’ve been fielding questions about my recent sea star spawning work from people I’ve shared this blog with, which is a lot of fun! To streamline things and make the info available to anybody who might be following, I decided to put together a very brief FAQ-like post to address the most recent questions.

Question:  Can you watch the eggs divide in real time?

In a time-lapse sense you can watch cleavage divisions occur, but not in real time. What I can do is set up a slide on the microscope and leave it there for a while. The gradually warming temperature speeds up development to the point that I can sort of see the division in real time. Of course, the danger is that the embryo will cook on the slide. I generally figure that once I’ve pipetted some embryos onto a slide and dropped a cover slip on top of them, they’re goners (it’s not really possible to remove the cover slip without damaging the cells underneath it) so I feel marginally less bad about sacrificing a few to the gods of observation.

Questions:  I’m fairly certain that the stars can go back to the sea, but are you able to keep their eggs with them, too? How difficult is that transport?

Actually, my scientific collecting permit specifically states that I’m not allowed to return animals to the wild. If I needed to, I could apply for additional permits but it has never been necessary for the work I do. Surplus eggs and larvae, therefore, are discharged into the seawater outflow at the lab and do return to the ocean but the parents remain in my care.

Question:  Are orange and purple stars usually able to cross with each other?

As far as anyone has been able to determine, the color of stars has zero effect on whether two individuals’ gametes are able to do the nasty together. The sea stars that I’m working with–Pisaster ochraceus, the ochre star–are broadcast spawners, meaning that each individual spews his/her gametes into the water, where fertilization and development occur. The stars are also synchronous spawners, meaning that if one individual in an area begins spawning other stars in the immediate vicinity will also spawn. After all, it does take two to tango, and to spawn while nobody else does is a tremendous waste of energy.

So yes, a purple star and an orange star should be able to mate without any problems… at least not any problems due to the parents’ colors.

Question:  If so, what color do they end up being, statstically?

This is a very interesting question. Two of my colleagues are going to spawn Patiria miniata (bat stars) next week to address this. Their plans are to cross a Blue female with an Orange male, an Orange female with a Blue male, and both pure-color matings. They did a preliminary version of this experiment a couple of years ago but didn’t end up with enough juveniles at a size that color could be ascertained; thus they couldn’t calculate any statistically meaningful color ratios.

Questions:  Do you suppose that the wasting disease could be now in the genetic makeup? Any thoughts (unofficial of course) about this?

My thought is sort of the opposite, actually. The animals that we brought in from the field are all survivors of SSWS; if anything, I’d expect them to be resistant to whatever causes the plague, and to (hopefully) pass on this resistance to their offspring. Of course, there’s no way of knowing if and how exposure to SSWS affects the quality of the gametes. It’s quite possible that these survivors are less fit after the SSWS outbreak than they were before.

Question:  Purple Male with Purple Female developed well and purple Male with Orange female didn’t…some sort of incompatibility?

Well, given what I saw today the Orange (female) x Purple (male) cross almost certainly did not work. Fertilization occurred, but almost none of the embryos had any indication of normal development. Since we know the Purple male was able to mate successfully with the Purple female, we can infer that his sperm were fine. It could be that there was something going on with the Orange female’s eggs; there were a lot of them, but maybe their quality just wasn’t very good. Or perhaps we somehow mistreated and wrecked them the other day.

Any other questions? Use the Comments section to ask them, and I’ll address them in a future post.

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Strangeness abounds

Posted on 2015-06-032023-01-06 by Allison J. Gong

Wow, they weren’t kidding about “early developmental asynchrony” in sea stars! This morning I looked at the embryos that I had started almost 24 hours earlier, and noticed two things right off the bat:

Thing #1:  Within the F1 x M1 (Purple female x Purple male) mating , developmental rates among full siblings were all over the map. Some embryos had progressed to the blastula stage, which is essentially a hollow ball of ciliated cells, while others were still in the early cleavage stages and rather a lot hadn’t divided at all. In fact, with 24 hours of hindsight I can see that several of these eggs had not even been fertilized.

Embryos of Pisaster ochraceus, age 24 hrs. 3 June 2015. © Allison J. Gong
Embryos of Pisaster ochraceus, age 24 hrs
3 June 2015
© Allison J. Gong

My first reaction upon looking into the microscope and seeing all these assorted blobs was, “Oh, crap.” But then I looked more closely at some of the embryos and realized that they had become blastulae!

Here’s a picture of a blastula. This embryo is freely swimming inside its fertilization envelope, although it doesn’t have a lot of space (remember that narrow perivitelline space from yesterday? that’s all the elbow room it has). The hollow space in the center of the embryo is the blastocoel ‘sprout cavity.’ Given that the embryo hasn’t grown (or even hatched) yet, it’s still ~165 µm in diameter, the size of the original egg.

Blastula of Pisaster ochraceus, 3 June 2015. © Allison J. Gong
Blastula of Pisaster ochraceus
3 June 2015
© Allison J. Gong

The stage that precedes the blastula (a hollow ball of cells) is called a morula (a solid ball of cells). The embryo that is partially visible in the bottom of the above photo may be a morula. Imagine the following sequence of events: (1) an egg is fertilized by a sperm, forming a zygote; (2) the zygote undergoes a number of cleavage divisions, with the cells becoming more numerous and smaller in size; (3) at some stage a solid ball of small cells, the morula, is formed; (4) as cell division continues, the cells migrate toward the outside of the sphere, forming a cavity (the blastocoel) in the middle.

The blastula is a ciliated stage, and in this video clip you can see the cilia moving. I shot this video at only 100X magnification to capture as much depth of field as possible, and suggest viewing at full-screen. This should enable you to see the three-dimensional structure of the embryo, and that it is indeed a sphere.


Thing #2:  The F2 x M1 mating (Orange female X Purple male) isn’t doing well at all. I looked at several slides and didn’t see any embryos that were developing normally. They had all been fertilized, as I could see the fertilization envelope surrounding each egg, but most had not even divided. The ones that had divided were all strange and just plain wrong. Here, see for yourself:

24-hr embryos of Pisaster ochraceus, 3 June 2015. © Allison J. Gong
24-hr embryos of Pisaster ochraceus
3 June 2015
© Allison J. Gong

Many of the eggs are blurry because they’re below the focal plane of the microscope. But see how many of them are undeveloped? And how, in the ones that have started dividing, the cells are disorganized and of different sizes? Typical echinoderm cleavage, as I see in echinoids (our local urchins and sand dollars) and in my other crossing of these ochre stars, results in a blastula made up of cells that are all approximately the same size. Most of these embryos, on the other hand, appear to consist of one large cell and a bunch of tiny ones.

I assume that these abnormal-looking-to-me embryos will not hatch, although I could be pleasantly surprised tomorrow. I don’t yet have much of an intuition about these Pisaster ochraceus embryos, so this is a huge learning experience for me. I do expect to see hatching in the F1 x M1 cross tomorrow. Fingers crossed!

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From zero to cleavage in. . . nine hours

Posted on 2015-06-022023-01-06 by Allison J. Gong

A recent college graduate and fellow marine lab denizen (Scott) and I are collaborating on a project to quantify growth rates in juvenile Pisaster orchraceus stars. This is one of the intertidal species whose populations in the field and in the lab were decimated by the most recent outbreak of sea star wasting syndrome (SSWS). We are interested in seeing how quickly the stars grow once they metamorphose and recruit to the benthos, and hope that the information will help researchers guesstimate the age of the little stars that are now being seen in the field. This would in turn tell us whether the little stars are survivors of SSWS or post-plague recruits. I keep seeing people refer to them as “babies,” but they could very well be several years old. We just don’t know, hence this study.

Large, healthy specimen of Pisaster ochraceus at Davenport Landing. 20 May 2015. © Allison J. Gong
Large, healthy specimen of Pisaster ochraceus at Davenport Landing
20 May 2015
© Allison J. Gong

But before we get to measure juvenile growth we have to get through larval development, which is perfectly fine by me because I’m always up for observing marine invertebrate larvae. Two weeks ago Scott and I ventured into the field in search of prospective parents. We brought back eight individuals from two different sites, making sure to leave many more in place than we took away. It was actually rather gratifying to see how many hand-sized-or-larger P. ochraceus there were. This morning we met at 07:30 to shoot up the stars with magic juice and then wait for them to spawn.

We have injected the stars (Pisaster ochraceus) and are waiting for them to spawn. 2 June 2015 © Allison J. Gong
We have injected the stars (Pisaster ochraceus) and are waiting for them to spawn
2 June 2015
© Allison J. Gong

It has been a while since I tried to induce spawning in Pisaster, and I had forgotten how much longer everything takes compared to the urchins. For one thing, the magic juice itself isn’t the same stuff that we use on the urchins, and works by an entirely different mechanism. The stars’ response to the magic juice takes 1.5-2 hours, whereas if the urchins aren’t doing anything 30 minutes after getting shot up they either need another injection or simply don’t have gametes to share.

However, despite my misgivings the animals spawned. Two large females gave us enormous quantities of eggs, and three more donated trivial amounts that we didn’t end up using.

This purple individual is the one we designated Female 1. See the huge piles of salmon-pink eggs?

Large purple female Pisaster ochraceus, spawning. 2 June 2015 © Allison J. Gong
Large purple female Pisaster ochraceus, spawning
2 June 2015
© Allison J. Gong

and

Large orange female Pisaster ochraceus, spawning. 2 June 2015 © Allison J. Gong
Female 2, a large Pisaster ochraceus, spawning
2 June 2015
© Allison J. Gong

Although we had to wait for a male to spawn, we finally did get some sperm and fertilized the eggs at about 12:30. Another thing I had forgotten was that Pisaster eggs, when shed, are lumpy and strange. I was used to the urchin eggs, which are usually almost all beautifully spherical and small. The stars’ eggs are about twice as big, at ~160 µm in diameter. The lumpiness doesn’t seem to hamper the fertilization process, as you can see below.

Fertilized eggs of Pisaster ochraceus, 2 June 2015 © Allison J. Gong
Fertilized eggs of Pisaster ochraceus
2 June 2015
© Allison J. Gong

In this photo you can see the fertilization envelope surrounding most of the eggs. In stars the perivitelline space (the space between the egg surface and the fertilization envelope) is very narrow, which makes it difficult to see the envelope; in urchins the space is much larger, and as a result the envelope quite conspicuous. The rising of the fertilization envelope off the surface of the egg is referred to as the slow block to polyspermy, a mechanical barrier that keeps multiple sperms from penetrating any individual egg. There’s also a fast block to polyspermy, but it happens on a molecular level milliseconds after a sperm makes contact with the egg surface; you can’t see it happen in real time.

Cleavage in stars proceeds much more slowly than it does in urchins, too. In embryological terms, “cleavage” refers to the first several divisions of the zygote, during which the cell number increases as the cell size decreases. This inverse relationship between cell size and number logically has to occur because the embryo can’t get any larger until it has a mouth and begins to feed, which won’t happen for at least a couple of days. It took our zygotes about four hours to undergo the first cleavage division.

2-cell embryo of Pisaster ochraceus, 2 June 2015 © Allison J. Gong
2-cell embryo of Pisaster ochraceus
2 June 2015
© Allison J. Gong

I left the slide on the microscope to warm up and speed development a bit, and about 45 minutes later was rewarded with this mishmash of embryos at different stages. Nine hours after we started this whole process, there were 2-cell, 4-cell, and 8-cell embryos, as well as eggs that had not divided yet.

Embryos of Pisaster ochraceus, about four hours post-fertilization. 2 June 2015 © Allison J. Gong
Embryos of Pisaster ochraceus, about four hours post-fertilization
2 June 2015
© Allison J. Gong

This asynchrony in early development is another way that stars differ from urchins, and it takes some getting used to. I expect that development will become more synchronized as the embryos continue to cleave, and that hatching will occur for all of them at about the same time, probably before Thursday. At least it won’t take another 9-hour day to see how far they’ve come.

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Crystals in the sky

Posted on 2015-05-312023-01-06 by Allison J. Gong

Early this afternoon the clouds at the marine lab were very interesting, so I took some photos:

© 2015 Allison J. Gong
© 2015 Allison J. Gong

These thin wisps are a subset of cirrus cloud called cirrus uncini clouds, commonly referred to as mares’ tails and characterized by the hooked formation (‘uncinus’ is Latin for ‘hook’). They occur high in the atmosphere, at altitudes around 5500 meters (18000 feet) and above, and consist of ice crystals rather than liquid water or water vapor.

© 2015 Allison J. Gong
© 2015 Allison J. Gong

Alas, cirrus clouds do not produce precipitation at ground level. Nor does their presence necessarily indicate a change in prevailing weather conditions. However, a large gathering of cirrus clouds may be a sign of an approaching storm front. The cloud formations I saw today dissipated within a few hours to a vague high-altitude haze. Meanwhile, my old friend the low-altitude marine layer appears to be re-forming over Monterey Bay, which means we’ll probably have an overcast night and a drizzly morning tomorrow–typical summer weather for the central California coast. It shouldn’t be very windy, and if the pattern holds for the next several days I might not freeze or get swept away when I go out on the low tides towards the end of the week.

© 2015 Allison J. Gong
© 2015 Allison J. Gong

Sometimes clouds are just so pretty!

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Sea urchins have no manners

Posted on 2015-05-212023-01-06 by Allison J. Gong

On Monday of this week (today is Thursday) I was transferring my baby urchins into clean bowls as I always do on Mondays, and for some crazy reason decided that I needed to measure all 300+ of them. I don’t remember how the details of how this decision came about, but it probably went something like this:

  • Me #1:  You know, we should probably measure these guys. We do want to see how fast they’re growing, after all.
  • Me #2:  Are you kidding? Do you know how long it’s going to take to measure 300 urchins under the microscope? We don’t have that kind of time today!
  • Me #1:  Oh, come on, don’t be so lazy. How long can it take, really? Let’s do it for science!
  • Me #2:  These things always take twice as long as you think they will.
  • Me #1:  It’s not as though you have anything better to do this afternoon. I mean, aside from writing a final exam and grading all those research papers you assigned.

Three-and-a-half hours later, Me #2 was soundly kicking Me #1 in the butt and we were all tired. But the urchins got measured and now I have some baseline data so I can track further growth. And, no, I don’t have the urchins separated into individual containers so I won’t be following individual growth, but will be able to calculate average growth rates across the cohort.

Having to look at each urchin long enough to get it lined up with the ocular micrometer in the dissecting scope gave me a chance to observe how their colors are developing. In the field, urchins of this species (Strongylocentrotus purpuratus) in this size range (mm-3 cm) are usually greenish in color; when these individuals are brought into the lab they turn purple as they continue to grow. I seem to recall that my last batch of lab-grown urchins (in Spring 2012) didn’t go through that green phase as juveniles, at least not as vibrantly as what we see in the field. So while I was holding down the current batch of urchins to measure them, I noted their color.

Some of them have a definite green tinge at the base of the spines, which then fades to a mauve-y purple towards the tips. The green coloration is most evident on the younger spines:

Strongylocentrotus purpuratus juvenile, age 118 days. This individual has a test diameter of 2.7 mm. 18 May 2015. © Allison J. Gong
Strongylocentrotus purpuratus juvenile, age 118 days. This individual has a test diameter of 2.7 mm
18 May 2015
© Allison J. Gong

In addition to giving the urchins something more substantial than scum to eat, having them on coralline rocks gives me a chance to see some of the other critters that live on the rocks. This particular rock is inhabited by a number of spirorbid polychaete worms that build tiny circular tubes made of calcium carbonate, as well as assorted small barnacles cemented to the rock and other crustaceans crawling around.

This is a close-up shot of one of the spirorbid worms. The tube is entirely covered by pink coralline alga, but the worm’s orange tentacular crown and trumpet-shaped operculum (used to close the tube when the worm withdraws) are extended as the worm filter-feeds:

Spirorbid polychaete worm on coralline rock, 18 May 2015. © Allison J. Gong
Spirorbid polychaete worm on coralline rock
18 May 2015
© Allison J. Gong

Another photogenic animal that I happened to find was a very small chiton. By the time I found it after measuring all the urchins I didn’t have the brain energy to try and key it out; if I can find it again once I’ve finished grading final exams I’ll give it a shot. It is extremely cute, with its bright blue spots, and was very slowly creeping around on the rock when one of the urchins barged in and ran right over it:

The chiton is probably about 4 mm long, just a bit longer than the urchin’s test diameter. To the urchin, walking over a chiton isn’t much different from walking over a rock; and while the chiton probably doesn’t like being walked on it isn’t significantly affected by the incident unless the urchin starts gnawing on it. Chitons are the masters of just hunkering down and waiting for things to get better, whether that means the tide coming back or an uncouth urchin moving along and minding its own business.

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And we have fledged!

Posted on 2015-05-152023-01-06 by Allison J. Gong

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.

Buteo jamaicensis (red-tailed hawk) father (left) and newly fledged offspring (right), 14 May 2015. © Allison J. Gong
Buteo jamaicensis (red-tailed hawk) adult male (left) and newly fledged offspring (right)
14 May 2015
© Allison J. Gong

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!

Buteo jamaicensis (red-tailed hawks), newly fledged juveniles (left and lower right) and adult female (upper right), 14 May 2015. © Allison J. Gong
Buteo jamaicensis (red-tailed hawks), newly fledged juveniles (left and lower right) and adult female (upper right)
14 May 2015
© Allison J. Gong

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!

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I’m famous!

Posted on 2015-05-142015-05-23 by Allison J. Gong

Well, fame is all relative, right?

VICE magazine’s May 2015 issue is focused on environmental crises of various kinds. One of the feature articles is on sea star wasting, which I’ve blogged about before, beginning in September 2013. The author of the VICE article, Nathaniel Rich, came out to the marine lab and interviewed me and some other folks back in February, and a photo crew came out to do a shoot in March.

Here’s the article. Overall I think Nathaniel did a good job; this is one of the better lay person articles I’ve read about wasting. He was able to convey the concern we biologists have about wasting, and the effects it could have on the ecology of the intertidal and subtidal marine habitats, without being too alarmist.

There is one glaring mistake in the first part of the article, which I’m positive must be a misunderstanding of something that I may have said to him. Can you find it?

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Almost branchers

Posted on 2015-05-112023-01-06 by Allison J. Gong

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!

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