'Doc' Ed Ricketts, no PhD:
California's Most Famous Marine Biologist

Excerpts from Ed Ricketts' 1939 Book, Between Pacific Tides, page 193 to 201,
Published by Stanford University Press, 320 pages

1939 Excerpt of Doc Ed Ricketts:
"Since the eelgrass, Zostera, occurs on flats of many types, from almost pure sand to almost pure muck, it seems desirable to list the animals associated with this seed plant before going on to the mud-flat forms. The start of a bed of eelgrass is an important step in the conversion of a former ocean region into wet meadow land and, ultimately, into dry land. The matted roots prevent the sand from being readily carried away by wind and tide, provide permanent homes for a less nomadic tribe of animals than inhabit the flats of shifty sand, and enrich the substratum with decaying organic matter until it can be classed as mud. The grass supports a rather characteristic group of animals that live on the blades, about the bases, and among its roots in the substratum."

Excerpts on Eelgrass by 'Doc' Ed Ricketts:
269. "In El Estero de Punta Banda we have found small and delicate sea urchins crawling about on the blades of eelgrass, possibly scraping off a precarious sustenance of minute encrusting animals but more likely feeding on the grass itself. They are so pale as to be almost white, but with a faint coloring of brown or pink. This urchin, Lytechinus anamesus, is known from shallow water in the Gulf of California and from the west coast of the peninsula. The largest recorded specimens are just over an inch in diameter. Ours are less than half an inch. They resemble bleached, miniature, purple urchins."

270. "In an adjoining eelgrass pond in the same region were many thousands of small snails, the high-spired Nassarius tegulus (Pl.XXXIX), also known as Nassa and Alectrion. Apparently these dainty little snails lead a precarious life, for about half of their shells were no longer the property of the original tenant, having been pre-empted by a smaller hermit crab, probably a new species of Pagurus."

"These snails and hermits, and the urchins mentioned in the previous paragraph, were all seen in winter. The summer sunlight and temperature conditions in this region being decidedly unfavorable, it is likely that every animal able to do so would move down-ward beyond the chance of exposure. It is quite possible that El Estero, which we have not visited in hot weather, might then be a relatively barren place."

"Many of the little Nassarius shells, whatever their tenants, are covered with white, lacy encrustations of the coralline bryozoan, Idmonea californica. On a superficial examination the erect, calcareous branches of this form cannot be distinguished from tiny staghorn coral. It is fairly common in southern California, and it will be quickly noted wherever found and almost certainly mistaken for a coral. When it encrusts on Nassarius it makes the shells at least half again as heavy."

271. To be continued.

272. "Associated with the eelgrass of Elkhorn Slough, and probably elsewhere where the bottom is compact, sandy mud, there is a skeleton shrimp, Caprella scaura. It is large, even by comparison with C. kennerlyi (>89) of the rock-pool hydroid colonies. Sometimes great numbers of them may be seen at night in the beam of a flashlight, under the surface of the water. Occasionally they will be found even on shores of pure sand. We take them also from mud bottom at 60 or 70 fathoms in Monterey Bay. As would be expected, this muddy-water form lacks the bright colors of the tidepool shrimps."

273. To be continued.

274. To be continued.

275. To be continued.

276. "The southern scallop, Pecten latiauritus, is commonly seen at Newport Bay and southward, attached to eelgrass clusters or swimming about their bases after the peculiar manner of the scallop tribe. It differs from P. circularis (Pl. XXXVII) in being flatter and in having wider "ears" at the hinge line."

277. To be continued.

278. To be continued.

279. To be continued.

280. To be continued.

281. To be continued.

282. To be continued.

283. To be continued.

Reflections & Observations
Robert 'Roy' J van de Hoek
Field Biologist & Geographer
Wetlands Action Network, Director of Research and Restoration
December 5, 2001

The section of Doc Ed Ricketts' 320 page book, Between Pacific Tides, that focused on Zostera marina, or Eelgrass, was just 9 sweet pages. However, those 9 pages are rich in nature descriptions on the natural history of the marine invertebrate animals that live on Eelgrass. There are 15 numbered sections, indicated by a special symbol as . The unique numbering system is cross-indexed in Doc Ricketts' book. For Eelgrass, it runs from 269 to 283, so you might think that 15 animals are discussed, however, within each section, there are several ecologies discussed regarding various associates, symbionts, and mutualistic ecological interactions. In a rough estimate of the 9 pages, I counted 41 marine invertebrates that were discussed in those 15 on those sweet nine pages. If one looks at Doc Ricketts' 320 page book in its entirety, it will be noticed that there are 338 sections, 1 to 338. There must be more than 500 animals that are discussed in Doc Ricketts' Between Pacific Tides.

There is also a sense of geography, as 'Doc' Ricketts takes us from Ensenada at El Estero de Punta Banda, to Alaska at Sitka's Jamestown Bay, then back to California at Elkhorn Slough, and then to Washington at Puget Sound. By the time you read the 9 pages, you have learned a great deal about Eelgrass and its marine associated animals, but you've also traveled nearly the entire Pacific coast. I've personally seen the Eelgrass beds at Ensenada and Elkhorn Slough, but it makes me want to travel to Washington and Alaska to see those Eelgrass meadows too. My interest is really perked now, for a field trip to Ensenada in summer to see if Ricketts' hypothesis about the marine animals on Eelgrass being either absent or much lower on the Eelgrass plants bears out any pattern. Recently, I've learned that the Great Blue Heron depends on fish that live in Eelgrass meadows near Vancouver, Canada, from the book by Robert Butler entitled: Great Blue Heron.