Cool as a sea cucumber

Cool as a sea cucumber

Sea cucumbers made news not long ago for a new conservation effort in Sri Lanka. It seems they’ve been over-harvested in many tropical regions across the world.  This came as a surprise to me – I saw quite a few while snorkeling in Hawaii. It turns out some sea cucumbers are being depleted – it’s not so much that they taste good; they’re said to be so bland they’re often boiled in meat broth to add flavor.  But they  contain some unusual nutrients, and their resemblance to a certain human anatomical part has given them an unfounded reputation for increasing virility.

Let’s hope sustainable practices prevail, because there’s plenty to admire about living sea cucumbers. Belonging to the class Holothuroidea, they stand out among the other classes in the phylum Echinodermata. Starfish are a good example of a “typical” echinoderm – radially symmetrical, with five arms (pentameral symmetry).  Echinoderms are, in general, pretty slow-moving. Most travel on tiny feet – tube feet — which are operated hydraulically, using the water vascular system that is another unique feature of this phylum.

Unlike other echinoderms, sea cucumbers have adopted a worm-shaped (or really, sausage-shaped) body plan. But the five divisions of the body are still evident, separated by grooves, ridges, or rows of tube feet, running lengthwise along the body.  Their elongated, five-part shape can indeed bear a remarkable resemblance to  a cucumber, although the color varies widely.

Sea cucumbers bear five sticky tentacles, which they use to collect organic matter, either from the sand or drifting down through the water.  These they insert alternately into the mouth, to pull off food particles. Because the mouth is often occupied, the other end of the digestive tube has become their main respiratory organ.  The sea cucumber’s anus, opening and closing as it breathes  throughout the day, has proved too inviting for the pearlfish to resist.  This long, narrow fish, with a pointed tail, has evolved just the right body shape to easily retreat into the sea cucumber for safety.

But perhaps the strangest thing about the sea cucumber is its ability to expel many of its internal organs when harassed. The benefits are debated, but it likely serves as a distraction in many cases – similar to  a lizard’s tail tip that breaks off when attacked.  Afterward, the sea cucumber slowly regenerates its discarded organs.  There’s plenty of diversity in when, why, and from which end, evisceration occurs.  Sad to say, none of this deters the sea cucumber fisherman.  But we can all do our part to prevent these vulnerable creatures from being driven to extinction — I’ll have my cucumbers from the garden, please.

The zebra spider around your home

The zebra spider around your home

The zebra spider, Salticus scenicus, is more common and fascinating than many people realize.  Check your window screens and outside walls — I often find they are conspicuous in the first warm days in early spring, but you can find them throughout the warm months.  Like all jumping spiders (family Salticidae), they are fun to watch.  You may find one feeding on an insect that is much larger than the spider.

Many liberties were taken with the caricatures in this drawing, of course, but I think it captures the outsize personality that these spiders project.  They are actually even smaller than shown — only a few millimeters.  But they are among the most interesting creatures easily observed around the home.

In explaining how spiders jump, I put “blood” in quotes because, like arthropods in general, they have an open circulatory system.  This is a system where, like ours, a fluid is pumped by the heart and travels through blood vessels; but unlike ours, it then leaves the open end of the blood vessels to circulate throughout the tissues of the body, where it is analogous to the interstitial fluid (and subsequently lymph) in humans.  Therefore in spiders, the term hemolymph is used to describe the circulating fluid.

You can learn more about the life of zebra spiders at Animal Diversity Web, and Bug Guide is a good general source for identifying this and other spiders. An excellent “jumping-off” point for those intrigued by jumping spiders in general is, where you will find links to blog posts about jumping spider-collecting expeditions (with beautiful photos), and to information about laboratory research on acoustic communication among these otherwise highly visual spiders.

The private life of earthworms

The private life of earthworms

Every summer I am shocked, simply shocked by the wanton hedonism that transpires in my tomato garden.  Sometimes, I have seen several pairs of earthworms mating simultaneously.  Last night was the first pair that I’ve noticed so far this year, so I guess the “season” has begun.  When you think about it, earthworms are probably the largest animals that most of us are likely to observe in the act of mating — at least, on a regular basis.

A good source for earthworm information is Earthworm Watch. There are a variety of sources for earthworm facts & trivia online — here’s one with a high density of information, and another with some surprising information about their ecology.  You may also be interested in earthworm toilets, which were in the news just a few months back (those are toilets for people, not for the earthworms).

Owls in the suburban web of life

Out here in our neck of the Colorado Front Range, it’s been a good year for great horned owls.  Two owl families set up shop within a few minutes’ walk from home.  One was in a nest hole that’s been used in past years, but the one shown here used a new site in a broken tree top.  Dinner for the owlets included rabbits as well as snakes, voles, and doubtless other critters.

The owls draw quite a crowd at times, indeed often more than a half dozen people, along with their dogs, and cameras of various sizes. There were experts with huge lenses, who seemed like they were out there several times a day, and casual dog-walking (but also camera-toting) visitors like myself.  When a lot of people converged on the owl site, it got harder to get a good camera angle, but it became a festive occasion on its own account.

Great horned owls have been increasing in Colorado. I had certainly never seen so many of them until I moved here. Even outside the spring breeding season, there are a few times when I saw several adults just on a casual walk through the neighborhood. The other thing we have a lot of are rabbits. At times, it seems almost every lawn has a rabbit in full view; it’s like an all-you-can-eat rabbit bar. So, I have assumed that this partly explains the abundance of owls.  But according to the Colorado Breeding Bird Atlas, the increase of great horned owls in Colorado has coincided with a decline of the long-eared owl, likely due to competition.  So, not all the owl species are happy — despite the rabbit bar.

Pangolins can’t wait 11 months

If you enjoy strange and whimsical-looking creatures, then pangolins are definitely for you. These tropical mammals look like something out of a kids’ cartoon fantasy, perhaps a cross between a dinosaur, and a fish out of water.  They have been one of my favorite animals since I first saw illustrations of them in books as a kid.  They are hard to find in zoos, perhaps because they specialize on ants and termites. During one of my visits to the San Diego Zoo some years ago, they kept a pangolin in the behind-the-scenes collection, but it was only brought out occasionally, and not during my visit. Finally, on a trip to Taiwan, to my great delight I found a pair of pangolins in a regular exhibit at the Taipei Zoo. There’s something about a bizarre beast like this that never seems real until you finally witness them going about their business, with your own eyes.  They were every bit as engaging as I could have imagined — exploring their surroundings with energy, playing with toys in the exhibit.

You may have already heard that pangolins are the world’s most trafficked animal.  So, we all need to celebrate these creatures, and make it known that we value them, before it is too late.  World Pangolin Day happens every February, but I don’t want to wait another 11 months to tell the world about them!

You can visit the Pangolin Blog at and cheer on (and donate to) the organizations that are working for pangolins.  And, you can get creative, as I have tried to do, and celebrate pangolins in your own way.

From —

12 things you can do to help pangolins on World Pangolin Day and beyond:

  1. TWEET using the hashtag #WorldPangolinDay
  2. LIKE the World Pangolin Day Facebook page
  3. BLOG about pangolins on World Pangolin Day
  4. SHARE pangolin information on your social media networks
  5. CREATE pangolin art — paint, draw, sculpt, tattoo
  6. EDUCATE by giving a presentation about pangolins at school
  7. SUPPORT organizations which are working to protect pangolins
  8. HOST a World Pangolin Day party or event (post your photos on the World Pangolin Day page!)
  9. BAKE cookies or a cake in the shape of a pangolin (post your photos on the World Pangolin Day page!)
  10. REQUEST full enforcement of laws and penalties for smuggling pangolins (and other wildlife)
  11. INFORM traditional medicine prescribers that the use of pangolin scales is illegal (and there are no proven health benefits to consuming scales — they are made of keratin, just like fingernails!)
  12. NOTIFY the authorities if you see pangolins for sale at markets or on restaurant menus, or if you know of anyone capturing or possessing pangolins.