Readers’ wildlife photos

We have two contributors today. First, some marine lovelies from Jacques Hausser in Switzerland. His notes are indented:

I’m just back from Britanny. Switzerland is a landlocked country and we lack close contact with the sea. Thus each spring we organize an optional two weeks internship on coastal ecology and faunistics at the Biological Station of Roscoff for the masters students in ecology and evolution. I started it forty years ago and I still happily contribute, ten years after my retirement. It is always an happy moment, turning up boulders, shoveling and sieving sand, helping students identify the collected animals – and also enjoying local seafood, cider and pancakes. Here, in a perfect taxonomic disorder, are some photos of our findings taken in the lab—I tried to suppress any  backgrounds.
Yes, it is an animal, and more, a mobile one. The rosy feather starAntedon bifida, is a Crinoid, a very ancient class of the phylum Echinodermata (sea urchins and starfishes). It usually clings on the rock or on an alga with the longish hooks (cirri) under its central part. You can distinguish some of them between the ten arms.  But it is able to swim if necessary with alternate movements of its arms (https://www.youtube.com/watch?v=O2zzv8LHjcw). As with many marine animals (and unlike any terrestrial one), it is a suspension feeder: it catches small particles in the water and they are brought to the mouth along a ciliated groove in the underpart of the arms.
It doesn’t look like one, but the tiny broad-clawed porcelain crab, Porcellana platycheles, is a filter feeder. It maintains a water current by permanently  waving its mouthpieces, and filters its food with long setae (bristles). Its impressive claws are used only in territorial (and sexual ?) competition. Quite flattened, it lives mostly under stones. And, by the way, it is not a crab (Brachioura) but a relative of hermit crabs and squat lobsters (Anomaloura). Easy: only 3 pairs of visible walking legs and long antennae. 
Compare with a real crab, the hairy crab, Pilumnus hirtellus: four pairs of walking legs and very short, almost invisible antennae. This small, omnivorous species is found mainly in the holdfasts of laminarian algae and is probably very “misocrabic” or at least territorial: I have never found two of them in any given holdfast.
The smile of the sap-sucking slugElysia viridis, an Opisthobranch mollusc. Algae don’t have sap, as far as I know). It feeds on green algae, specially Codium, and, interestingly, is able to spare the chloroplasts of the alga and tosequester them in the cells of its back, where they continue to photosynthetize for the benefit of the slug. The “ears” are rightly called rhinophores (nose-bearers), they detect smell rather than sound. You can see the tiny eye just behind the left one. Although this individual is rather contracted, you can also distinguish the small iridescent blue spots that adorn the animal. 
I call it “Mister No body”. Nymphon gracile is a Pycnogonid or Sea spider, and actually a very remote cousin of spiders and scorpions, a Chelicerate (or even possibly a sister group to every other arthropod). It has so little space in his body proper that its digestive tract must expand itself into the legs. It is a rather eclectic predator, eating sessile prey like sea squirts, sea anemones and other hydrozoans, and even snail eggs. This one is a male: you can distinguish the faintly visible translucid ovigerous legs used to carry the eggs (yes, it is the male’s duty in this species).
It is mesmerizing to observe the movements of the tentacles of Eupolymnia nesidensis, a polychaete worm of the family Terebellidae. They seem absolutely autonomous, exploring every aspect of their environment, retracting, expanding, changing direction or sticking to the substrate with a very good imitation of free will. They are U-shaped in section, which forms a ciliated canal along which tiny particles of food are brought back to the mouth. The red “bushes” are gills used for the respiration, and between the gills and the tentacles you can notice a collar of tiny black eyespots. The worm lives in a self-made mucous tube glued under a stone and encrusted with gravel and sand.
It is not as spectacular as its exotic cousins we have recently seen on WEIT, but I nevertheless like the tiny Limacia clavigera, the orange-clubbed sea slug, is a nudibranch mollusk. It browse on sea mats like Electra pilosa and probably sequesters some toxic molecules from its prey into the yellow-clubed “cerata” each side of its body (a frequent habit in sea slugs with aposematic warning colors). It is able to autotomize these cerata to distract a would-be predator (examples of reduced cerata on the left side), but they regrow in a few days. Notice the rasp-like rhinophores and the three tiny yellow gills between the forelast pair of cerata. 
Tritia reticulata, the netted dog whelk (formerly called Nassa reticulataHynia reticulata and Nassa reticulata again – the lack of stability of the zoological nomenclature sucks). It is a necrophageous snail, the real vulture of the beach. With its long respiratory siphon, it looks like a vintage steam engine, but the siphon is very useful considering its habit of burying itself in the sand. It is able to detect any dead animal a long distance away (at least one meter in an aquarium) and reacts very quickly. Note that the eye is at the basis of the tentacle, not at the tip like in the terrestrial snails.

And reader Christopher Moss snapped some snowshoe hares in his Nova Scotia garden.  They’re changing color back to their warm-weather fur, so are appropriate to post today.

Two new visitors today, Lepus americanus, which I have not seen in the garden before. One is beginning to recover the brown hair of summer, and the other is still pretty much a pure white. They are sitting in the same spot, but are two different creatures! First the white one came along and had a sniff at some branches.

The the brown flecked one turned up. Lovely!
Playing hide and seek with me:

20 Comments

  1. Posted March 21, 2018 at 8:09 am | Permalink

    Nymphon gracile is impressive. All of the sea creatures have so much information about physical mechanisms for adaption…it boggles my mind.

  2. Terry Sheldon
    Posted March 21, 2018 at 8:19 am | Permalink

    Love both sets of photos! Special thanks for all the information about the various invertebrates. The star and “sea spider” in particular are amazing.

  3. Mark Sturtevant
    Posted March 21, 2018 at 8:22 am | Permalink

    Mesmorizing! I very much enjoyed all of these.
    Jacques, how did you take pictures of specimens under water without recording bright reflections from the surface of the water?

    • jacques.hausser
      Posted March 21, 2018 at 11:48 am | Permalink

      Never using a flash! I have two Manfrotto Lumie led lights, one to the left and one to the right, and I move them until it is OK. The animal is in a plastic bowl on which a sprayed matt white paint. (with the black background I did the same, but it is less efficient).

    • Jacques Hausser
      Posted March 21, 2018 at 11:52 am | Permalink

      Never using a flash! I have two Manfrotto Lumie led lights, one to the left and one to the right, and I move them until it is OK. The animal is in a plastic bowl on which a sprayed matt white paint. (with the black background I did the same, but it is less efficient).

    • gravelinspector-Aidan
      Posted March 23, 2018 at 2:33 pm | Permalink

      A waterproof camera works too!
      A technique I’ve seen reported, but not used myself is to take a translucent white plastic hemisphere – a bowl by any other name – and cut a hole in the base to accommodate the lens of your camera. Place the bowl over the subject (down to the waterline in the wet), and photograph away for a very “flat,” low shadow illumination.

  4. Merilee
    Posted March 21, 2018 at 9:09 am | Permalink

    Great photos, Jacques and Christopher! Love Mr. No Body.

    • Posted March 21, 2018 at 1:02 pm | Permalink

      Me, too! And it was a hard choice for a favorite, as there are so many awesome ones new to me!

  5. George
    Posted March 21, 2018 at 10:08 am | Permalink

    A pic of PCC(e)’s ducks. A picture of the Botany Pond taken on Monday or Tuesday and posted on the UChicago Admission’s Instagram Account. The ducks are floating on the water. The red thing on the bridge is supposed to be maroon and is a phoenix. UofC’s seal features a phoenix rising from the ashes. Not sure why he/she/it is on the bridge. Not sure if it is a person in a costume or an inflatable thing.

    • Posted March 21, 2018 at 10:24 am | Permalink

      My ducks!!! They are far more enticing that that damn inflatable phoenix. Sadly, I haven’t seen them for two days: it’s been cold and there are workman doing sidewalk repair near the pond, which makes them skittish.

  6. Christopher
    Posted March 21, 2018 at 10:16 am | Permalink

    Quite lovely. Thank you for sharing.

  7. Mark R.
    Posted March 21, 2018 at 12:12 pm | Permalink

    “Mr. No Body” is a perfect name, made me smile. All the inverts were amazing and thanks for the interesting commentary.

    Lovely snowshoe hairs; in the last standing photo, you can really see their big mits: aptly named.

  8. Posted March 21, 2018 at 12:15 pm | Permalink

    Eupolymnia nesidensis: could the tentacles *be* autonomous to some degree? Like having a separate nervous system somehow?

  9. Jonathan Wallace
    Posted March 21, 2018 at 12:17 pm | Permalink

    Wonderful creatures and great photos of them Jacques!

  10. Posted March 21, 2018 at 1:20 pm | Permalink

    Great photos, Jacques and Christopher. Thanks.

  11. jaxkayaker
    Posted March 21, 2018 at 1:46 pm | Permalink

    Excellent photos! Let there be more non-insect invertebrate photos!

  12. Posted March 21, 2018 at 6:47 pm | Permalink

    Great pics! The photosynthetic sea slug looks kinda cute.

  13. Diane G.
    Posted March 22, 2018 at 12:19 am | Permalink

    Great photos of some fascinating inverts, Jacques, enhanced all the more by the accompanying descriptions! (Not to mention wry comments nomenclature. 🙂 )

    Christopher, congrats on adding such a charismatic new animal to your garden fauna! How fortuitous that you were in the right spot at the right time (and with decent lighting!) to get such charming pics of them. 🙂


%d bloggers like this: