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Tidal creatures of the night

Creatures of the Night

This Friday, Nov. 25 at 10:45 p.m., the new-moon tide will ebb to a rare low of -3.4 feet. Taking this opportunity to explore an island community normally hidden from view, the Vashon Beach Naturalists will host a free Starlight Low-Tide Walk at the north-end ferry dock from 9-11 p.m. Sip a hot chocolate as you head to the beach with a naturalist guide to discover dozens of denizens of the intertidal zone: nudibranchs (sea slugs), sea cucumbers, and sea pens to name a few.

A shaggy mouse nudibranch (Aoelidia papillosa). Photo taken near Pt. Vashon by Kathryn True

A shaggy mouse nudibranch (Aoelidia papillosa). Photo taken near Pt. Vashon by Kathryn True

Besides the fact that our local winter low tides occur only at night, this is a good time to get out for several reasons. At low tide on a hot summer day, animals that prefer cold, wet, and dark are stressed out and doing their best to hide. They’re in their comfort zone after dark, when you’re more likely to find light-sensitive creatures like octopuses. Also, animals tend to venture out of their designated tidal zones at night, making them easier to observe.

Intertidal secrets in the spotlight

With your visual field reduced to the circle created by a flashlight, it’s easier to focus your attention on every little detail…there’s incredible diversity to be discovered within one 12-inch diameter spotlight! Scour every rock closely to find animals like chitons—masters of camouflage these mollusks are hard to distinguish from the rocks they inhabit. Look for their oval shells made up of eight overlapping armor-like plates.

Vashon Beach Naturalist Sally Ammon says the highlight of the walk would be finding the evasive red octopus. She’s looking forward to seeing sea pens, which are often found near the end of the ferry dock. Belonging to the octocorals, or soft corals, these colonizing animals look like orange feather plumes sticking out of the sand; they have hundreds of eight-tentacled polyps on each of their soft “branches.” Beach visitors are sure to find crabs, sea cucumbers, limpets, and sea stars. Careful observers might also detect a telltale bump in the sand that indicates a hidden moon snail—these common local gastropods have a pretty round shell and an enormous pink, fleshy foot that can grow to three times the size of the shell. Moon snail mothers secrete their eggs in a gelatinous sheet that becomes coated with sand, leaving a donut-shaped ring behind. The resulting “sand collars” found on local shores each hold about a half-million moon snails-in-the-making.

Sunflower seastar (Pycnapodia helianthoides) found on a previous low tide evening. Photo by: Kathryn True

Sunflower seastar (Pycnapodia helianthoides) found on a previous low tide evening. Photo by: Kathryn True

Respect for beach dwellers

Whenever you visit the beach, remember these beach naturalist guidelines to help protect the health and safety of our intertidal neighbors: Don’t walk on eel grass or in tidepools, wet your hands with saltwater before touching the animals to protect their sensitive skin, return animals to where you found them, don’t move a rock larger than your head, and carefully replace any rocks you move.

Want to read up on what to look for? Two of Sally’s favorite field guides are Whelks to Whales: Coastal Marine Life of the Pacific Northwest, and Pacific Reef& Shore: A Photo Guide to Northwest Marine Life, both by Rick M. Harbo.

If you can’t make it this Friday, take a virtual beach walk with these resources from the Seattle Aquarium: http://www.seattleaquarium.org/page.aspx?pid=862. Look for some of the creatures mentioned in this post in their “Marine Invertebrate” Powerpoint.

Walk logistics: Park in the north end ferry parking lot and walk down the hill to meet the naturalists at a tent across from La Playa. Dress warmly in layers, bring raingear, and wear sturdy, non-slip boots. Bring a flashlight with a strong, directed beam (lanterns do not work as well), and an insulated cup to fill with hot cocoa.

If you go and get some great pictures send them along to us at Vashon Nature Center: info@vashonnaturecenter.org

HAVE FUN!!!!

Coyotes on Vashon

Vashon has always had an almost mythic connection to music. An inordinate number of musically inclined people find themselves drawn to these shores. Music surrounds children growing up here. As a child, I remember hearing flutes in the woods as I walked home from school, and the haunting notes of marimbas floating through my bedroom windows on warm summer nights. It’s no wonder that many children here eventually become musicians themselves. Even Vashon’s nickname, Dancing Man, hints at the music coursing through this place.

Earlier this summer I awoke just before dawn to a new song in the woods. In my just awakened state I thought of the flutes and marimbas of my childhood. But, as my surprise wore off, it slowly dawned on me what these howls were.  I lay there appreciating the irony that coyotes, known as “America’s Native Song Dogs,” had found this island.

I saw my first coyote on Vashon in July of this year. However, these “song dogs” were first sighted at least six years ago according to T Martino of Wolftown who first positively identified a dead coyote near St. John Vianney’s.  She notified the Beachcomber so that people would be aware of their presence. After a lull in sightings, T says she has had several sightings on both ends of the island for the past three years.  Vashon Nature Center has also had several south-end sightings reported this summer and fall.

 

This picture was taken near Camp Sealth on November 11, 2011. This was one of 2 coyotes seen. Photo by: Nik Ormseth

This picture was taken near Camp Sealth on November 11, 2011. This was one of 2 coyotes seen. Photo by: Nik Ormseth

 

This scat, possibly coyote, had tapering ends typical of canids and was full of fur and mice bones (seen just to the left and in front of the human thumb). Seen October 14, 2011 also near Camp Sealth. Photo by: Orion Knowler

This scat, possibly coyote, had tapering ends typical of canids and was full of fur and mice bones (seen just to the left and in front of the human thumb). Seen October 14, 2011 also near Camp Sealth. Photo by: Orion Knowler

How do they get here? Probably just like deer and the occasional bear do. They swim. Perhaps across Colvos passage since that would be the shortest distance. Deer regularly swim across from Colvos and coyotes are reported as better swimmers than deer.

And why are they appearing now?  Like our raven populations that have increased over the last decade, coyotes may be making a comeback because there is more habitat for them as old farmlands convert back to forests.  We don’t know for sure if coyotes inhabited the island in the past or are recently returning after a hiatus. There are no known records one way or another from early settlers of the islands. Coyotes are spreading to many rural areas both because of habitat change and because they were successful at filling the space left open when wolf populations were extirpated across most of the lower 48.

What does it mean for the island to host this “native song dog”?  No one knows yet. Hearing coyotes in our midst seems to generate both a sense of excitement and nervousness, especially for cat and small dog owners. Just like eagles and great-horned owls, coyotes can kill cats though they aren’t their preferred food.

Possible coyote benefits

From an ecological viewpoint coyotes stand to be helpful here. Their most common and preferred source of food is small rodents of all kinds. T Martino thinks that they may also occasionally take young or sick raccoons and fawns, which could help to balance these populations. A secondary effect of balancing deer populations may be a more diverse understory of plants in our forests.

A few people who live where coyotes have been sighted have mentioned to me that their raccoon population seems to be dwindling. Whether this is an actual drop in raccoon numbers or a behavioral change on the part of these animals responding to coyote presence, or something entirely unrelated to coyotes (like Leptospirosis infection), no one knows. But who wouldn’t be glad for a reprieve in the endless battle to come up with increasingly sophisticated barricades for the garbage cans?

Keys to co-existence

There are real and effective actions people can take to increase the chance that coyotes and other island residents continue to live harmoniously.  Rural residents have successfully demonstrated this in communities across British Columbia, California, and Colorado.  These successes result when humans work within the constructs of coyote societies to establish behavior patterns that are passed from one coyote generation to another.

 Keeping these naturally shy animals shy and wild is the key to harmony. 

Below are proven effective techniques from Project Coyote, a coalition of wildlife biologists working to increase co-existence of humans and coyotes.

1.       Do not feed coyotes.

2.       Walk pets on a leash (especially during spring and early summer when pups are in dens and coyotes may try to deter you or your dog).

3.       Supervise small pets and children and keep cats inside (keeping cats indoors also helps native songbird populations).

4.       Secure garbage, compost, and pet foods.  (Make sure can lids are tight, pick up fallen fruit, feed pets inside, and prevent bird feeders from attracting rodents.)

5.       “Haze” coyotes seen near homes and community spaces. (Pop open your umbrella, blow a whistle, make a shaker to use, or just be BIG and LOUD in any way you can).

6.       Talk to your neighbors. See a coyote in your neighborhood? Ask neighbors to follow these tips to make the area less attractive to them.

7.       Secure livestock. Use guard dogs, guard llamas, or secure fencing.  Locally, Wolftown also suggests electric fencing around chicken coops. Wolftown is a great local resource for livestock owners who want to learn preventative techniques.

Coyote myths

There are a few myths about coyotes worth mentioning. First, coyotes do not carry rabies. Russell Link, who works for Department of Wildlife and Fish in Washington and has authored many books about urban wildlife, says that bats are the only wild animal in Washington that carry rabies and very few bats actually do.

Secondly, culling coyote populations does not work.  Numerous studies show that coyote populations explode in response to killing for a number of reasons. Let be, coyotes have a rigid social structure in which only the alpha pair breeds. However, if the social structure is upset, more coyotes in the pack start to breed. This leads to higher than normal population growth.  In addition, young animals may have less guidance as to how to behave if key older pack members are shot. This can lead to unwanted coyote behaviors becoming established in a coyote population that is growing at an unstable and rapid rate.

Evidence from the past six years of coyote habitation on Vashon Island suggests that our coyote population is blessedly shy and wild. Most of us don’t even know they are here.  Working together as a community to continue to reinforce this behavior will help minimize potential conflicts.

I enjoy the fact that these high clear voices are part of Vashon’s ever-changing song. When I listen, I think of the benefits to our island ecosystems that those voices potentially symbolize.  I accept that they have made it to this island to live a life and call it home just like I did. And I will do everything I can to keep in right relation with these bards of the woods, including securing my food and scraps and animals, and scaring them off if needed for everyone’s sake, including theirs.

Please report coyote sightings or any possible coyote interaction with pets/livestock to Vashon Nature Center: info@vashonnaturecenter.org

For more information on coyotes please contact Vashon Nature Center or Wolftown. For specific information on securing livestock, contact Wolftown and consider donating to their cause.

Beetle Mania!

I was on a walk last week and noticed two joggers stopping to ponder something on the ground at the edge of the pavement. I had just rescued a woolly bear caterpillar (the larval stage of the Isabella Moth) from a suicidal road-crossing and thought they’d found another one of these relatively cuddly critters.

 

Vashon style- accessorize with woolly bears! Photo by: K. True

Vashon style- accessorize with woolly bears! Photo by: K. True

What I discovered instead was orange and black like the woolly bear, but the similarities stopped there. Far from cuddly, this was an inch-long beetle covered in miniscule wriggling mites. Gary Shugart, collections director at the Slater Museum of Natural History in Tacoma, had recently told me about similarly colored carrion beetles he’d found in a deer carcass he was preparing. He regaled me with stories of the rather macabre and definitely fascinating natural history of one of nature’s more colorful undertakers.

A “nose” for death

My beetle did turn out to be in the carrion beetle family (Silphidae), in the genusNicrophorus, most likelyNicrophorus marginatus. In Greek, necro means death and phor means bearing. The common name for this group is the sexton beetles, a sexton being a church’s groundskeeper and gravedigger.

 Carrion Beetle, notice the hitchhiking mites! Photo by: Kathryn True

Carrion Beetle, notice the hitchhiking mites! Photo by: Kathryn True

Sexton beetles do bury their carrion, but not for reasons associated with an afterlife. Also known as “burying beetles,” these insects tend carcasses for food and as part of an unusual reproduction ritual.

Carrion beetles can locate a dead animal within an hour of its demise (up to 1.5 miles away!) using highly sensitive olfactory organs in their antennae.  Observe my beetle’s handsome orange-topped smellers. Once they locate the deceased, if it’s the appropriate size (they prefer small vertebrates including birds and rodents) they will bury the carcass to protect it from flies and other carrion competitors (crows, raccoons, flies, fungi, and bacteria to name a few), preserving the feast for themselves.

Breeding Nicrophorus beetles use a small carcass as a sort of wedding bed/nursery combined. After one beetle has found the perfect corpse, it uses pheromones to attract a mate. For the next 24 hours the two work together to bury the dead, stopping intermittently to mate…up to 70 times. The female then lays her eggs in the carcass, and the happy couple stays together to raise their young (feeding them on regurgitated animal remains)—an example of co-parenting rare in the insect world.

Hitch-hiking mites

Another strange and remarkable carrion beetle natural history note relates to the mites teeming over their bodies. From the genus Poecilochirus, these tiny insects have developed a co-dependent relationship with the carrion beetles. The mites get a free ride to their next meal (they eat the eggs and larvae of carrion flies)…an essential transport service considering how difficult it would be to get from one dead thing to the next when you’re only 1 mm long and you can’t fly! The carrion beetles benefit as well  because the mites gobble up the carrion competition, preserving more food for the beetles and their young.

There is very little information out there about what insects live on Vashon/Maury and the parts they play in island ecosystems. Help us learn more: Meet any beguiling beetles lately? Send your photos or descriptions to us at info@vashonnaturecenter.org.

Information for this post was found on this useful insect identification website Bug Guide and from an insect database at University of Nebraska.

Happy bug hunting!