No. 66–Flowers of the Sea, Part I
Coast of Oregon 1981, fourth month of the last great road trip in the old painted Rambler and ten years before the serendipitous founding of the North Street Aquarium.
All my life, from family vacations to youthful wanderings to present travels, I have been immediately and inextricably drawn to the nearest water be it pond, creek, lake or ocean to see what there is to see. So it was the first mist hung morning in Newport where the rocks and tidal pools revealed and imprinted images of understated yet captivating beauty that remain in my mind’s eye today.
What caught my attention at the time and intrigues me today were sea anemones. Phylum Cnidaria, class Anthozoa order Actiniaria; there are approximately 1,000 extant species of anemone. They come in many shapes, colors and sizes and while some species are found in deeper waters, the majority inhabits coastal shallows and estuaries.
Most were introduced to anemones through the hugely popular film (having had no kids I haven’t seen it) “Finding Nemo”. The down side of the film was the explosion in the popularity of clown fish and their anemone hosts with aquarium hobbyists.
The ensuing rush to make clown fish anemone species available to the pet trade resulted in the wide spread deaths of untold thousands of anemones in their collection, shipping to distributors, intermediate holding and shipping to retailers and inadequate care at the retail level. The vast majority of those that survived died in commercial display or home aquariums within two years.
While it does appear that growing public understanding of and appreciation for the need to protect the habitats and species of what are known collectively as “marine ornamentals, the threat of over harvesting coral reef ecosystems to meet the demands of the salt water aquarium market persists.
General anemone morphology may be described as column shaped body attached, in most cases, to a hard substrate by a sticky pedal disc. At the business end of the column is the oral disc with tentacles surrounding the mouth. The tentacles are armed with stinging cells with the duel purpose of capturing prey and warding off predators. They have limited mobility in that they are able to creep, something like a snail, on their pedal disc.
One of the local species residing at the Estuarium is the non-estuarine hermit crab anemone Calliactis tricolor. Many anemone species have symbiant relationships as with 26 species of anemonefish and 10 species of anemone that serve as hosts. C. tricolor is known to hook up with the flat-claw hermit crab Pagurus pollicaris found near shore and the giant red hermit crab Petrochirus diogenes usually found in deeper waters. Though more rarely, it has also been observed riding the striped hermit Clibanarius vittatus.
Tricolors are known to wash ashore after storms. The Estuarium’s current and previous specimens were found on Hunting Island. Stranded and closed up tight on the beach they have the shape of a chocolate covered cherry.
C. tricolor is not a particularly visually striking animal as anemones go. Ours stands a little over two inches when fully extended with a circumference roughly that of a quarter coin and its column is a mottled reddish-brown and cream mix. Around 200 opaque relatively short, 1/4 to 3/8 of an inch, surround its mouth.
Laboratory studies indicate that the physical pairing of hermit crab and anemone is sometimes a mutual effort with the crab prying the anemone from a substrate and the anemone obligingly attaching itself to the crabs shell. Other times the anemone will approach on its own and climb onto the shell. Hermits have also been observed transferring anemones to new shells they move into.
The cohabitation arrangement is mutually beneficial in that the stinging cell armed anemone provides an added defense for the crab and the anemone benefits from the bits of food wafted into its tentacles as a result of the crabs messy eating habits.
Well now, once again I see I have broached a subject that can’t be covered in a single issue. We will return next month more on anemones in general and local species in particular.