Yes, I know... Valentine's Day was two days before this column will be published (how's that for mixing tenses?). However, smart guys like me realize that Valentine's Day candy goes on sale at Vons the day after so you get a much better deal for next year's gift to your sweetie... if there ever is a sweetie! So I see nothing wrong with sending my readers, at least those of the female persuasion, a few roses this week. Maybe next year I won't spend the day alone! In the past, I've found that sending a lovely lady a dozen red roses has never worked for me. Perhaps if I actually signed the card that went along with them it might help. A starving marine biologists can't afford them anyway, unless they are "day old." So this year I'm sending a few substitutes... rose anemones... to the ladies who read this column.
Like me, anemones are often overlooked. As Rodney Dangerfield would say, they just don't get no respect. Tidepoolers step on and squish them as they look for more brightly colored starfish and nudibranchs. Perhaps it's because they, like their Cnidarian relatives the corals, use their mouth as their anus. How could any self-respecting human accept that? But rose anemones are quite beautiful if you overlook that simple fact of their digestive tract challenged lives.
The white spotted rose anemone is about 4" in diameter and up to about 6" high. It is crimson (go Harvard!) in color and the base has many white spots arranged in rows. Because of this, it is sometimes called the strawberry anemone... hmm, that conjures up some romantic thoughts as well. Chocolate dip anyone? The tentacles are also crimson and lack any markings or bands. The mouth/anus is located in the center of the ring of tentacles. This region is not as intense in color as the rest of the anemone.
Anemones are radially symmetric. Their body structures are arranged as if they were spokes on a bicycle wheel. Unlike their coral relatives, they have no hard structures to support their soft bodies. Instead they rely on water pressure when they need to firm up! Water is taken into the digestive cavity and held there, creating a more rigid body. The more water they take in, the firmer they become. I guess this is similar to middle age guys like me that suck air into their lungs and pull in their paunch to attract the ladies... at least for a few seconds at a time! If they are exposed at low tide, the rose and other anemones become very limp.
Although I've introduced this anemone within a romantic context, their sex life hardly mirrors that! In fact, they primarily reproduce asexually by budding, at least once an anemone is established at a location. How boring. They do use sexual reproduction as a means of creating larvae which can drift with the currents and colonize new areas. That's kind of like casting your children out of the house at an early age to seek their fortunes. One scientific study indicated there were more females than males in a population, although about 15% of the collected specimens lacked gonads altogether. It appears that spawning is triggered in early winter as water temperatures drop from their maximum.
Anemones, like the other members of the phylum Cnidaria, contain stinging cells used to capture food and for defense. Yes, I realize that is not very romantic... but you must get by the thorns to pluck rose flowers, so deal with it. Little is known of this beautiful species' natural history. Since anemones are carnivorous, their food probably consists of invertebrates, small fish and other organic matter that drifts within reach of their tentacles. In northern tidepools they have been observed eating crabs and starfish. In turn, anemones may be eaten by predatory snails or fish. Of course there is no commercial "fishery" for them and florists are not known to grow or harvest them for this special day.
The rose anemone is a circumpolar species, meaning that it can be found in waters adjacent to the northern hemisphere pole. It is found on both sides of the north Atlantic. On our coast it is known from Alaska to southern California. While our waters can be chilly due to the cold, south-flowing California current, I don't really consider them polar. The rose anemone does illustrate an interesting point about biogeography, the study of the distribution of plants and animals on Earth. It is at the southern most end of its distribution here because its distribution can expand due to the influence of the major oceanographic current. On the Atlantic coast, it is restricted to more northerly waters because the warm Gulf Stream flows up that coast.
Although I have seen rose anemones in several places around Catalina, they are always at colder water locations like Ship Rock and Farnsworth Bank (where these pictures were shot). Since our waters are among the warmest in the Channel Islands, this makes sense given their cold water affinities. Rose anemones are limited to rocky surfaces they can attach to. Most scientists state they are found from the intertidal to about 75 ft depths. The beautiful specimen observed at Farnsworth Bank on a recent dive off the King Neptune was at a depth in excess of 100 ft. This suggests they may be found in the deeper, colder waters at this southern end of their range.
This past weekend I had the pleasure of diving three sites with buddy Amy, a biologist and tech diver from Asia and California. Bob & Tina Kennedy were sure trying to look out for me! However, Amy has a fiancee and lives in Korea, so our time did not extend far past the water's edge. Sigh! After another "cold" Valentine's Day, I'm hoping this column will brighten my prospects for next year. At least I get to eat all that Valentine's Day chocolate I bought at Vons the day after!
© 2006 Dr. Bill Bushing. Watch the "Dive Dry with Dr. Bill" underwater videos on Catalina Cable TV channel 49, 10:00 AM and 5:00 PM weekdays. Please help me climb out of self-imposed poverty... buy my "Munching and Mating in the Macrocystis," "Great White Sharks of Guadalupe," "Calimari Concupiscence: Mating Squid, "or "Giant Sea Bass" DVD's. Yes, take Dr. Bill home with you... we'll both be glad you did!
The beautiful white spotted rose anemone at
wishing all my lovely readers a Happy Valentine's Day!
This document maintained by
Dr. Bill Bushing.
Material and images © 2006 Star Thrower Educational Multimedia