Biology of the Red , franciscanus, and Its Fishery in

SUSUMU KAT0 and STEPHEN C. SCHROETER

Introduction Canada and the United States to answer quested information to help them devel- some of these needs. This report pre- op fisheries for their of sea Since Kat0 (1972) reported on the sents relevant information from the urchins. beginning of the sea urchin fishery in literature, much of which is not readily California, it has grown dramatically. accessible to persons in the industry, as Description of Sea Urchins The catch has exceeded 11,OOO metric well as from our own investigations. A Sea urchins belong to the phylum tons (t) in 1981 in California, and up to review of , Strongylocen- Echinodermata, which also includes 500 t have been harvested in 1 year in trotus franciscanus (Fig. l), biology is starfish, sea cucumbers, sea lilies, and Washington. Most of the product of the given to promote understanding of brittle stars. All sea urchins have a hard fishery, the roe (both male and female natural processes which can have a calcareous shell called a test, which is gonads), is marketed in Japan, where bearing on the commercial use of sea covered with a thin epithelium and is the sea urchins as well as the roe are urchins. Descriptions of the harvesting, usually armed with spines. The mouth, called “uni.” processing, and marketing sectors of the located on the underside, consists of five Inevitabky, development of the fishery industry are also presented. We hope calcareous plates called “Aristotle’s lan- has raised questions about the status of that this information will aid in main- tern” in honor of the Greek naturalist populations, and effects of the fishery taining a commercially viable and envi- and philosopher. The mouth leads to the on the urchins and environment. Be- ronmentally sound fishery for many digestive tract which empties through cause fishermen, processors, potential years. We hope that this report will fill the anus located on the top of the test. investors, and management officials all the needs of the hundreds of persons Five skeins of roe comprise the most require information, several scientific from throughout the United States as prominent structures in the internal studies were initiated by researchers in well as other countries who have re- cavity of sea urchins. Sea urchins are

Susumu Kat0 is with the Tiburon Laboratory, Southwest Fisheries Center, National Marine Fisheries Service, NOAA, Tiburon, CA 94920, and Stephen C. Schrceter is with the Department of Biological Sciences, University of Southern California, University Park, CA 90089.

ABSIRACT-The Californiajishery for the red sea urchin, Strongylocentrotus francis- canus, has grown steadily since its inception in 1972, and the mimum annual catch has exceeded 11,000 metric tons. Most of the producr of the jishery, the roe, is exported to Japan, though a significant amount is also consumed in the United Stares. This paper describes aspects of red sea urchin life history, distribution, abundance, ecology, and management. A detailed description of the jshery, including harvesting, processing, shipping, and markering methods, is also Figure 1.-The red sea urchin, Strongylocenrrotusfranciscanus (left), and the given. smaller purple sea urchin, S. purpurarus.

47(3), 1985 I unisexual, being either male or female, constituents are likely to change, de- found as deep as 125 m (McCauley and but cases of hermaphroditism (Le., with pending on the nutritional and reproduc- Carey, 1967). Individuals of both spe- both male and female gonads) have been tive states of the urchins. Sea urchin roe cies prefer rocky substrates, particularly recorded in several species (Boolootian also contains calcium, phosphorus, ledges and crevices (Schrc~ter,1978), and Moore, 1956). Between the skeins iron, Vitamins A, B,, BZ, Bu, nicotinic and avoid sand and mud. of roe are gill-like structures which are acid, pantothenic acid, folic acid, and Both species are often found in and part of the water vascular system, im- carotenes (Higashi et al. 1959, 1965). around stands of the giant kelp, Macro- portant in movement, respiration, and Since polychlorinated biphenols cystis spp., and other brown algae. Typi- food gathering. The gut is dark and (PCB) and other potentially toxic hydro- cally, sea urchins are most abundant often filled with partially digested plant carbons are of major concern to the near the outer edges of kelp beds and material. Japanese, an analysis was undertaken to less numerous inside (Pearse et al., Two species of sea urchins are com- learn the extent of pollution from these 1970; Low, 1975; Pace, 1975; Mattison mon in shallow coastal waters off Cali- noxious compounds. Red sea urchins et al., 1977; Tegner and Dayton, 1981). fornia: The red. S. franciscanus, and collected at Fort Bragg, Calif., in 1973 Adult sea urchins that live within kelp purple, S. purpurufus, sea urchins (Fig. were found to have no detectable beds are larger than those outside, and 1). Several other species also occur in amounts of DIYT, but contained an aver- recent recruits (

~~ ~~ Item 12 32 relative, the purple sea urchin, usually inside and outside of beds, but may suf- occupy shallow waters, from the mid to fer higher mortality in the former habitat Moisture 700 708 686 71 8 Protein 77 96 95 123 low intertidal zones to depths in excess (Pearse et al., 1970). Lipid 76 83 54 52 of 50 m, but red sea urchins have been Juvenile red sea urchins are frequent- Ash 16 15 13 17 Glycogen 13 17 ly found under the spines of larger red ~ Nonprotein IReuben Lasker, National Marine Fisheries Ser- urchins, and are scarce elsewhere in the nitrogen 01 05 01 05 vice, NOAA, La Jolla, Calif. Personal commun. same habitat (Low, 1975; Breen et al., ‘Sources. 1. Modified alter Greenfield el al , 1958: 2Katsutoshi Miwa, Tokai Regional Fisheries 2 from Krarner and Nordin, 1979: 3 Modified after Research Laboratory, Tokyo, Japan. Personal 1976; Tegner and Dayton, 1977; Schroe- Giese et ai, 1958 commun. ter, 1978). One possible explanation for

2 Marine Fisheries Review this distributional pattern is that larvae et al., 1974; Tegner and Dayton, 1981; along the west coast of North Anicrica. selectively settle in areas where adults Cowen, 1983). Annual recruitment rates of red sea ur- are abundant, and soon find shelter In and near the boundaries of kelp chins were lower and often more vari- under the larger sea urchins. This hy- beds, Tegner and Dayton (1977, 1981) able in British Columbia, Canada (Ber- pothesis was tested and rejected by and Tegner and Levin (1983) found nard and Miller, 1973; Breen et al., Cameron and Schroeter (1980), who bimodal size distributions which they at- 1978), than in southern California (Mit- conducted laboratory and field larval tributed to size-specific predation by chell et al., 1969; Pearse et al., iT/O; selectivity experiments with red and spiny and . Tegner and Dayton, 1981; Ebert, 1983). purple sea urchins. They concluded that Red sea urchins larger than 80 mm in The mechanisms underlying such pat- the pattern of juvenile distribution was test diameter are less vulnerable to terns are poorly understood, but latitudi- due either to increased survival rates predators because of their size; those nal gradients in temperature. predation. under adults, or to migration of young smaller than 50 mm take shelter from and disease, or interactions of these fat- sea urchins under adults following predators beneath the spines of adults tors have been hypothesized (Frank, settlement. Hinegardner (1969, 1975) or in cryptic habitats. Because shelter 1975; Fawcett, 1984). and Cameron and Hinegardner (1974) sites are relatively scarce for urchins be- Two other patterns of distributic found that the larvae of white sea ur- tween 50 and 80 mm (these are abundance are of interest to tho:,, .. n- chins, Lytechinus anamesus, selective- too large to hide under larger urchins), gaged in the red sea urchin fisher:. 2-i ie ly settle and metamorphose on bacterial they suffer high mortality. The mode of first is clumping, and the seis .; films. These films are ubiquitous larger sea urchins therefore consists of possible competitive interactioii> (Sheer, 1945) and are probably abundant those survivors which accumulate over already noted that red sea urcb!: inside as well as outside kelp beds. time. The other mode is made up often found in high abundance ~ir~wiid An hypothesis that higher mortality primarily of small sea urchins <2 years of larvae or juveniles inside versus out- old. side kelp beds accounts for patterns of Although bimodal size distribution juvenile abundance remains untested; (with only very small and large sea ur- however, the higher abundance of filter- chins being represented) can be explain- feeding organisms, known to eat sea ur- ed by size-selective predation in areas chin larvae, inside kelp beds suggests where spiny and sheephead are that predation of larvae may be signifi- prevalent. studies over many years by lumbia often occurred in group .ir cant (Pearse et al., 1970). the Kelp Habitat Improvement Project4 clumps of 50 or more. Smaller grtiups. The importance of predation after have shown that size distribution can as well as solitary sea urchins, tended settlement is suggested by a number of vary markedly in different habitats and to merge with the other groups until this studies which have identified sea urchin over time. Local populations in southern apparently critical number was reach- predators that are abundant inside or California consisted of all small or all ed. Low (1975) speculated that t:l~ir :!:- near the edges of kelp beds. These large individuals, and any number of ing may be a mechanism to incr predators include rock crabs, Cancer combinations of small, medium, and chances of fertilization, to coiiipc'. 11 spp. (MacGinitie and MacGinitie, large individuals (State Water Quality macroalgae for space. or for prut-.s-!it,n 1968); leather starfish, Dermasterias Control Board, 1964; Pearse et al., of adults as well as juveniles Fi-om imbricata (Rosenthal and Chess, 1972); 1970; Anonymous, 1977). Bernard and predators. sun stars, Pycnopodia helianthoides Miller (1973) also noted varied size dis- Interspecific competition between ab (Tegner and Dayton, 1981); agile sea tribution patterns for red sea urchins in alones, Haliotis spp., and sea urchins stars, Astrometis sertuliferu (Leighton, British Columbia where major predators is known to affect the distribution and 1966); bat stars, Patiria miniata of small sea urchins are not so prom- well-being of both groups. Abaloncs (Schroeter et al., 1983); and spiny lob- inent. Progressions in size distribution seem to outcompete sea urchins 5.w sters, Panulirus interruptus (Tegner and over time in a particular habitat have space (Lowry and Pearse. 1973: She;>-. Dayton, 1981; Tegner and Levin, 1983). been well documented by Pearse et al. herd, 193), although sea urchins liiay Among fishes, the horn shark, Hetero- (1970) and Ebert (1983) who found that be more efficient in feeding (Tqns-i-. dontusfrancisci (Limbaugh3) and wolf- food availability and rates of settlement 1980). In southern California, hoth eels, Anarrhichthys ocellatus (Bernstein and survival of juveniles were important groups prefer giant kelp, Macr I et al., 1981), have been observed to feed in determining distribution patterns. pyriferu, to other seaweeds (Lei on sea urchins. In southern California, The rate at which existing populations 1966, 197l), so competition for , however, the most significant preda- are replenished and the regularity of this likely to occur. Selective fishing fbr I - tor is the California sheephead, Semi- recruitment increase from north to south alones, both in Australia and, ir; :t: cossyphus pulcher (Quast, 1968; Feder past, in California, may have c'v- tributed to increases in numbers i>. --

~ 4W. K. Keck Laboratory of Environmental Health 'C. Limbaugh, 1959, personal commun. cited by Engineering, California Institute of Technology, chins (Lowry and Pearse, iV7.3; Leighton (1971). Los Angeles, Calif Shepherd, 1973). Under present condi-

47(3), 1985 3 ,972 13 71 71 76 I 78 79 80 81 8.2 83 Year

Figure 3 -Annual landings of red sea urchins in California Source Cali- forma Department of Fish and Game

duce their abundance. Because the two species compete, the selective removal of reds by the sea urchin fishery may cause an increase in the abundance of purples in the subtidal habitat. This in fact happened following small-scale ex- perimental removals of reds in the shallow subtidal zone. Any discussion of sea urchin distribu- tion would be incomplete without inclu- sion of the effects of predation on sea urchins by sea otters, Enhydra lutris. Once almost extinct in California, sea otters now inhabit much of the central California coast, and it is not coinciden- tal that sea urchins are scarce wherever sea otters are present. Sea urchins are among the most common food items of sea otters, and those sea urchins remain- ing in subtidal waters where otters are present are usually found deep in crev- ices (McLean, 1962; North, 1965; Leighton, 1966; E. E. Ebert, 1968; Figure 2.-A group of red sea urchins near kelp beds at Santa Cruz Island, Lowry and Pearse, 1973). southern California. No data are available on the abun- dance of red sea urchins along the California coast, but annual catch totals (Fig. 3) give some measure of harvest- able populations. At first glance it would tions in southern California, however, of purple sea urchins. The distributions appear that the California fishery environmental factors, as well as fishing of the two species overlap, but purples reached its harvest potential in 1981, pressure and predation on sea urchins- dominate in harsh habitats (e.g., mid- when 11,300 t were landed. The lower rather than on abalones-may be more intertidal and intertidal, as well as sub- catches in 1982 and 1983 may not have important than competition in determin- tidal habitats exposed to waves and been directly related to abundance of sea ing distributional patterns and abun- surge) while reds dominate in benign urchins, however, and the declining dance of sea urchins and abalones (Teg- habitats (sheltered habitats in the low catch may not signify that the maximum ner and Levin, 1982). intertidal and subtidal areas). Purples catch has been attained. Schroeter (1978) studied red and pur- are more abundant than reds in the A major climatological event, com- ple sea urchins near Santa Barbara, harsher habitats because they are more monly called “El Nitio,” occurred in Calif., and at nearby Santa Cruz Island, tolerant of physiological stress and wave 1982, affecting fisheries throughout the and concluded that competition for and surge action. Although purples ac- west coast, and indeed the whole Pacific space plays an important role in deter- tually prefer benign to harsh habitats, Ocean. Unusually warm water invaded mining the distribution and abundance reds outcompete them there and so re- the southern California coast and weak-

4 Marine Fisheries Review ened or killed keb. the maior food of where food was relativelv scarce. move- to Whites Point. Calif. (near Los An- sea urchins. Later in the year, severe ment averaged over 50 cm per day. Ex- geles). Pearse et al. (1970) found indica- storms associated with El Niiio finished perimental studies by Lees (1970) in tions of spawning between June and the job by tearing the weakened kelp Mission Bay in San Diego, Calif., also November. Most of the populations from the seafloor? The same storms showed that food scarcity stimulates the showed no large increases in gonad size made it impossible for divers to work movement of both red and purple sea ur- prior to spawning, and the gonad weight in the winter and spring of 1982-83. Too, chins. On the other hand. Silver and was usually less than IO percent of the during much of 1983 the roe yield of red Brierton (1974) found no mixing be- body weight. In these populations the sea urchins was lower than normal. tween two groups of red sea urchins gonads underwent a sharp decrease in often to the point of making processing which were located close together in weight during some time of the year. uneconomical4 The small gonads might depths of 3 and 11 m. separated by a however, indicating that the populations also be linked to lower feeding activity. nearly vertical rock face. The shallow had spawned. An exception was the For red sea urchins, feeding rate is group had an abundant supply of kelp, population at Point Loma. in San Diego. greatest at 16°C. The rate declines as the while the deeper group lived in an area Calif.. wihich maintained large gonads temperature increases (Leighton, 1971). with much less food and devoid of at- throughout the year (March 1969-March During most of 1982-83 bottom temper- tached kelp. 1970) and failed to show the marked atures were significantly above 16°C in decrease in gonad size which accom- Reproduction red sea urchin habitats (Shelton et al., panies spawning. This population was 1982). Several processors had to close Knowledge of sea urchin reproductive thought to throughout the year. their plants, while others continued biology is valuable to those conducting The Point Lorna population was the only operating at lower production levels. the fishery: the yield of roe is greatest one of those studied that existed in an Thus, whether or not the southern Cali- just before spawning when it may reach area with abundant food. fornia populations are presently being 20 percent of the total body weight. Baker (1973) also studied red sea ur- fished to their maximum potential is However, during the peak of reproduc- chins at Point Loma in 1972-73 and open to question. However, northern tive activity, uptake of water by the found a similar lack of a well-defined California fishing grounds have certain- gonads causes them to exude a great period in which the decreased gonad ly not been worked to any extent, and deal of gonadal material (Miller and weight indicated spawning. On the other expansion of the fishery is likely to oc- Mann, 1973). and the roe has low niar- hand, he found a lower gonad weight cur there when conditions warrant. ketability. Thus. the best quality roe is during summer in populations inhabit- found just before the onset of prolifera- ing nearby Mission Bay. Evidently the Movements and tion of sex cells and before the mature populations at the two areas were in dif- Aggregating Behavior gonads absorb water. After spawning, ferent physiological condition; gonads Patterns of movement and aggregation the gonads are small and the yield is too of Point Loma sea urchins averaged of red sea urchins are important to low for economic use, being SO percent 11.58-15.71 percent of the total weight of fishermen and resource managers. as or less of the peak yield (Kramer and the sea urchin throughout the year. moving hordes of sea urchins can some- Nordin, 1975). while those from Mission Bay sea ur- times decimate large fields of algae Increase in gonad size is actually chins averaged 8.60-10.75 percent. Ben- (Leighton et al., 1966; Leighton, 1971; related to feeding, rather than to some nett and Giese (1955) found a late Dean et al., 1984). In many cases, how- intrinsic reproductive cycle, and to stor- spring-early summer spawning season ever, red sea urchin populations are sta- age of glycogen (a carbohydrate) in the in central California: workers in Canada tionary and highly aggregated where gonads (Giese et ai., 1958). Bernard detected possible spawning periods from food is abundant; they are less aggre- (1977) explained the somewhat compli- spring to fall (Bernard and Miller, 1973; gated and move more when food is cated processes that occur during the Kramer and Nordin, 1975, 1979; Ber- scarce (Vadas, 1968; Pace, 197s; Russo. development of mature gametes, and nard, 1977). 1979; Harrold and Reed, In press). Mat- concluded that food availability is the A measurement commonly used to tison et al. (1977) found such a pattern key to synchronization of the reproduc- estimate a sea urchin’s reproductive state and documented differences in rates of tive cycle in red sea urchins. The repro- on a gross (nonmicroscopic) level is the movement. Movement of red sea ur- ductive events of sea urchins follow a “gonad index.” The index, a relative chins inside a kelp bed where food was more or less annual cycle, but there are measure of gonad size, is simply the abundant averaged about 7.5 cm per day. significant and interesting variations in ratio (expressed as a percentage) of the In comparison, in areas some distance the pattern. gonad weight or volume to the total from the kelp bed (15-100 m away) The spawning season of red sea ur- weight or volume of the sea urchin. An chins appears to vary depending on abrupt loss of gonadal bulk evidenced

~~~~ ~~~ locality and sometimes even from year by a decline in the gonad index indicates ’Ron McPeak, Kelco Co.. San Diego, Calif. Per- to year at the same place. In various that spawning has taken place. sonal commun. 6Neal Matsushita. S,M Uni co,,Los coastal localities from Papalote Bay, To determine the reproductive condi- Calif. Personal commun. Mexico (near central Baja California). tion of red sea urchins harvested by the

47(3), 1985 5 i 1 sai M x '6. - + I 1 n rn 14- c5 - c,"l '5 I m '. Spann output per z ; Sa+a +1 w 0 12- -

9' 10- - ";. '$ '$ Y 3:>- -

-e- 10- - 1974 I 1975 ic- - Spann output per ear as Figure 4.-Means and standard error for gonad indices percent 01 test votme of' commercially caught red sea urchins (percent gonad .- :>I' 7" weight of total weight of drained sea urchins). TEST DIAMETER (mml Figure 5.-Spawn output related to test diameter for the white sea urchin. Lyrechinus iruriegrrrus (after Moore et al.. 1963).

fishery, we calculated gonad indices (100 X gonad weight + drained body weight) of red sea urchins harvested in 1974-75 by commercial divers from the be most important. Divers often report percentage of test volume (Fig. 5. be- northern Channel Islands (Santa Cruz, that sea urchins near lush algal stands low). Thus. to assess the spawning po- Santa Rosa, and San Miguel Islands). have much larger gonads than in- tential of a sea urchin population, one When these samples were taken, spawn- dividuals located several meters away must know the relative abundance of ing was fairly synchronous among the where algae are scarce or absent. Others different sized sea urchins, as well as the different sites. The gonad indices were have also noted the importance of food amount of spawn produced by indivi- high from August to December, but they to the growth of gonads, which arc not duals in the size range. dropped from December to February only reproductive organs, but also sites Another reproductive process impor- (Fig. 4), thus indicating spawning dur- for food storage (Giese et al., 1958; Ber- tant to the sea urchin fishery is the ing the latter period. nard, 1977; Dean et al., 1984). length of time it takes for gonads to It should be noted that our samples The amount of gametes produced regain their bulk after spawning. Data were not representative of the whole (usually measured by size of gonads) we obtained from a commercial sea ur- population because spawned-out ani- may not be directly correlated with size chin processing firm in 1975-76 indicate mals are usually not collected by divers; or age of the urchins. Bernard and a rather protracted recovery period last- thus, on the whole, harvested sea ur- Miller (1973) indicated that red sea ur- ing from spring to early summer, after chins are likely to have a higher gonad chins in British Columbia probably first the sea urchins had spawned from index than the general population. Even spawn at age 2 at around 50 mm test dia- December through February or March. with this bias toward higher indices, the meter. We were able to induce spawn- On the other hand, Bernard (1977) found results clearly indicate a discrete spawn- ing in red sea urchins as small as 40 mm that in British Columbia the gonad in- ing period lasting at least from Decem- at Santa Cruz Island. The production of dex of red sea urchins returned to 80 ber through January. Red sea urchins gametes by these tiny individuals is, of percent of maximal levels by October, that we sampled from commercial land- course, very low. only 1 month after spawning. The go- ings in 1976 in northern California (Fort Bernard (1977) found that the ratio of nads attained their greatest size several Bragg) (unpubl. data) also indicated a gonad weight to shell diameter increases months later in May. Kramer and Nor- winter-to-spring spawning period. with size, until red sea urchins attain 95 din (1975). however, found an interme- The maximum gonad size attained mm; the ratio then decreases slightly. diate interval of time between spawning differs not only from locality to local- Moore et al. (1963) found similar results and recovery in their study of British ity (Leighton, 1967; Pearse et al, 1970; in their study of the east coast's white Columbia red sea urchins. The differ- present study, Fig. 4), but also from sea urchin, Lyrechinus variegurus. The ences may be due to the amount of food year to year at the same locality (Ben- total spawn output (Fig. 5, above) was available in the respective habitats. nett and Giese, 1955). The causes of this greatest for large sea urchins (but not variability have yet to be determined, the largest size class), but smaller sea Development and Growth but according to several sea urchin urchins were relatively more productive Development of red sea urchins from divers, differences in food supply may when spawn output was expressed as a fertilization through various free-swim-

6 Marine Fisheries Reiiew ming larval stages to settling of the many species of algae, they clearly pre- petitors. and owe their pcr\istcncc in the juvenile takes about 6-8 weeks, depend- fer the giant kelp, Macroqstis spp., community to the gwing acti\ it? of \ea ing primarily on water temperature when it is available (Leighton, 1966, urchins. Experimental rciiio\;iI of \ca (Johnson, 1930). Depending on a host 1971). Off the coasts of Washington and urchins often results in local competitive of environmental and genetic factors, British Columbia, red sea urchins pre- elimination of the less prelerred species young sea urchins can grow to sexual fer the bull kelp, Nereocystis leutkeariu of algae (Vddas. 1968: Paine and V;id~is. maturity between 1 and 2 years after (Vadas. 1968. 1977). 1969; Palniisano. 1975: Pearse and they settle on the bottom (Bernard and As one might expect, diets consisting Hines, 1979: Duggins. 1980). Miller. 1973; Tegner'). of preferred foods result in much higher The influence of sea urchin gra/inp Marks on hard parts have commonly growth rates (Leighton, 1971; Vadas, on giant kelp in southern Calitornia ha\ been used to study the age of animals. 1968, 1977). A striking demonstration received a great deal otattcntion. since In sea urchins, rings similar to those of this phenomenon can be found in sea urchins have been held responsible found in tree trunks can be seen in the southern California, where locally for the widespread disappearance of this spines, and growth lines or zones also dense populations of red sea urchins economically and environmentall> \alii- occur in the plates that make up the test. eliminated all fleshy algae. forcing in- able species (North and Pearse. 1970: Both have been used to ascertain the age dividuals to feed on less preferred and Leighton, 1971; North. 19774). Rescarch- of certain species (Jensen, 1969; Pearse nutritionally inferior encrusting coral- ers from the Calif&xia Department of and Pearse. 1975). Detailed studies of line algae (e.g., Lithotharmion spp. and Fish and Game. Scripps In~titutionof the formation of growth zones in the Bosiellu spp.). Sea urchins in such areas Oceanography, California In\titute of tests of purple sea urchins have dis- typically have only the rudiments of Technology, and KclcoX(a commercial closed, however, that rings or zones do gonads and appear to be starved (State kelp harvesting firm). and groups of not necessarily correlate with seasonal Water Quality Control Board, 1964). recreational diver< have worked on the phenomena, and are thus not useful for Plankton, as well as organic suspen- restoration of kelp beds tor over 20 indicating age (Pearse and Pearse. 1975). sions produced by sewage outfalls, are years. Almost without exception. at- Breen and Adkins (1976) reported simi- also utilized by sea urchins. In fact, the tempts to restore kelp fore\t\ have .rtart- lar negative results for red sea urchins, latter source seems to have relatively ed with the eradication of WLI urchin\, and our attempts using Jensen's (1969) high nutritional value, and may be the and successful results of sonic of thew methods failed to find reliable age in- primary factor responsible for persis- efforts seem to demonstrate that sc;i ur- dicators in the test plates. tence of dense sea urchin populations chin grazing is a principal reason tor Growth of red sea urchins. measured even after they have overgrazed and failure of giant kelp to become reejtab- by increases in test diameter, has been eliminated their normal algal food lished in certain habitats (Nor.th. M"). studied in the laboratory (Leighton. source (Pearse et al.. 1970). Finally, Of course, other factors wch as coiii- 1967, 1971). in cages in the field (Swan, when food is scarce or absent, sea ur- peting vegetation. other gra/ers. and 1961; Schroeter, 1978), and with un- chins can derive energy necessary for adverse environmental conditions also caged field populations (Baker, 1973; maintenance by resorbing their gonadal act to hold down help grouth (Wilson Bernard and Miller. 1973). The studies and gut tissues. et al.. 3978). indicated an annual growth increment of Feeding rates of red sea urchins are In areas where the \tanding crop of 13-25 mm, with smaller individuals influenced by temperature. The opti- algae is well established. sei1 urchin showing faster gains in test diameter, as mum feeding temperature is about 16"C, presence is not neccwiril\ detrimcntal expected. Thus, on the average, red sea and red sea urchins feed as long as the to the plant coniniunit) (Roscnthal et urchins probably attain harvestable size temperature remains between 6" and al., 1974), and removal of lary nuinhers (90-100 mm) in around 4-5 years. 25°C. In southern California, at depths of sea urchins may not affect the algal Many factors affect growth rates of where red sea urchins are most abun- abundance or distribution (f3ri.cn et 211.. sea urchins and the maximum size at- dant, bottom temperatures are general- 1978). tained by individuals in a local popula- ly higher and nearer the 16°C optimum From the point ot view ot those thr- tion. These include availability and nu- in winter than in the summer (Leighton, ing kelp propagation. it ij clear. that re- tritional value of algae, competition, 1971). duction in numbers of red sea urchins temperature, and the severity of wave would be beneficial. Indeed it ha\ even Ecology and Management and surge action (Bennett and Giese, been suggested that sea otters be rein- 1955; Swan, 1961; Ebert, 1967, 1968; As noted above, grazing by red sea ur- troduced into southern California for Leighton, 1971; Baker, 1973; Schroeter, chins has a profound influence on the this purpose. It would secni. however. 1978). types of algae that ultimately dominate that the commercial fishery is a more Food and Feeding a particular habitat. This is because sea satisfying means of controlling growth urchins prefer to eat certain species, Although red sea urchins feed on thereby leading to the dominance of the ~~~

~ 8Mention of trade name or comnierci:iI firm\ dw\ 'Scripps Institution of Oceanography, La Jolla, less preferred species. In some cases, not imply endorsement by the author5 or b) the Calif. Personal commun. the less preferred species are poor com- National Marine Fisherieh Sen ice. NOAA.

47(3), 1985 7 in populations of red sea urchins, which is during spring and early summer when in the financial centers-New York, are valuable renewable natural re- the roe yield is still rather low, as are Chicago, Los Angeles. San Francisco- sources. The fishery brings income to the prices in Japan. However. market the demand for exotic (at least to con- the industry as well as helping in some conditions do vary, and in some years ventional American tastes) fish products measure to lower our deficit in the bal- it has been profitable to export roe even increased. Much of the fare served in ance of trade of seafood products. On in summer. these restaurants was traditional Japan- the other hand, selective removal of red Not all processors and fishermen ad- ese, including raw fish and shellfish, sea urchins may allow growth in the vocate long seasonal closures of the fish eggs (including uni, or sea urchin population of purple sea urchins, which fishery. They point to the difficulty of roe), eels, jellyfish, and the like. Since can also cause overgrazing when large keeping key personnel during the off- many of these were not readily available numbers are present. These two species season, or counting on their return in the United States, they were imported overlap to a great degree (except at the when processing resumes, and also to from Japan. And, owing to the high cost shallow end of the range), and their food the fact that some good sea urchins can of air freight, most of these items were preferences are similar. be found throughout the year. Those transported by ship in the frozen state To maintain a long-term fishery, some firms that supply the domestic market which, although unacceptable in Japan. management measures may need to be especially need to operate throughout was the only form available in the instituted, for it is clear from studies by the year or chance the loss of their United States. Canadian researchers that recovery of markets to imports. In 1968, the NMFS Southwest Fish- exploited red sea urchin populations is The State of Washington has a rather eries Center started looking into the a slow process (Breen et ai.. 1978). In simple management system, whereby feasibility of developing a sea urchin the absence of regulations, divers should the coast is divided into three zones, one fishery to supply the growing domestic take it upon themselves to ensure that of which is closed to sea urchin fishing markets and for export to Japan. The enough large sea urchins are left in har- each year to foster repopuIation’9 In decision to try to initiate a fishery was vest areas to support recruitment of Japan, seasonal, depth, and gear restric- prompted not only by the demand for young urchins, which need the protec- tions are all used to help ensure against the product, but also because sea ur- tion afforded by the spines of larger in- overfishing, and habitat improvement chins were considered pests by kelp dividuals. Perhaps a maximum size programs are also employed to encour- harvesters, recreational fishermen, and limit would help in this regard. age settlement and growth of sea urchins the abalone industry. In fact. groups of Most persons involved in the Califor- (Mottet, 1976). sport divers regularly held organized nia fishery feel that management is call- In the absence of State-mandated “urchin kills,” whereby divers armed ed for to prevent damage to sea urchin fishery regulations, members of the with hammers would smash any and all stocks. One management option favored California industry might well impose sea urchins found in selected habitats. by many divers, according to two polls, self-regulatory measures to ensure the Quicklime (calcium oxide) was also is a limit on the number of persons future of the fishery. The collapse of the used to control sea urchins in commer- allowed to fish for sea urchins9. Some sea urchin fishery in northwest France cial kelp beds. Now, however, state reg- processors we interviewed also felt that in the 1960’s (Southward and South- ulations prohibit the use of quicklime economic returns should be considered ward, 1975) should serve as amble re- because of strong objections by sea ur- in any management scheme. For exam- minder to all that sea urchins are sus- chin divers and other fishermen. ple, they advocate closure of the fishery ceptible to overfishing, and the authors Since the processing of sea urchins re- during spawning season when the roe pointed out that sea urchins are impor- quires a large number of low-skilled is soft and unappealing, and until the tant for maintaining a balance in the workers, a new fishery also offered in- gonads recover to near maximum bulk. ecosystem. They plead: “The lowly sea creased employment opportunities for Since the precise time of spawning urchin is strongly in need of friends to such workers. Other advantages of a sea may vary from year to year and at dif- come to its rescue.” urchin fishery included reduction in ferent locations, however, it would be fishing pressure on abalone, possible History the Fishery unwise to set prescribed open and of improvement in the habitat for abalone closed seasons. Obviously, divers and In the 1960’s, a few individuals har- and other and fishes that processors have the best and earliest vested small numbers of sea urchins for depend on seaweed for shelter or food, knowledge of these events when they oc- home consumption and for the domestic and lowered deficit in the U.S. inter- cur, and it behooves them to work to- market in California. With increasing national seafood trade. gether to stop fishing in areas where numbers of Japanese restaurants open- In the early phases of development in gonad quality and quantity are low. ing in the United States to serve the 1972, we sent trial shipments of frozen Another period of marginal profitability growing Japanese business communities roe to Japan, the principal market. Be- cause the defrosted roe became soft and

~~~ unappealing due to cell rupture, no in- ‘“Richard Burge. Washington Department of Fish- =Parker, California Department of Ftsh and eries, Shellfish Laboratory, Brinnon, Wash. Per- terest was shown by the Japanese market Game, Long Beach, Calif. Personal cornmun. aonal commun. for the frozen product. Since the prevail-

8 Marine Fisheries Revim 124’W 122ow 12 W 120-w 118.W I I I A. North-Central Morro Bay B. Southern California California

Barbara

\ Los Anaelea 34”

38ON

Half Moon

Figure 6.-Major California fishing grounds (shaded) for red sea urchins

ing monetary climate prohibited air landings increased to 11,000 t in 1981, Table 2.-Annual Callfornla landing of aea urchin by district (percent of total landings). freight of fresh roe to Japan, we decided but declined somewhat in the next 2 years. The following sections describe San Santa to concentrate on supplying the domes- Eu- Fran- Mon- Bar- San San tic market while experimenting with the harvesting, processing, and market- Year rekal CISCO terev bara Pedro Dieao means of preserving the roe in better ing sectors of the California sea urchin 1973

47(3), 1985 9 Figure 7.-A 9.1 m (30 foot) Wilson drive boat; note the Figure 8.--Sea urchin collecting bag with rubber tube. two large mesh bags full of sea urchins.

made by Radon and Wilson (Fig. 7). mesh bag, about 2 m long, with a 1.4 Because of the hard physical labor, The vessels are made of fiberglass, m ring opening (Fig. 8). cold water, and pressure, divers are usually around 8-9 m long, and powered After the first batch of sea urchins is forced to surface often to rest, and ac- with diesel engines. The carrying capa- transferred, air is pumped from the tual diving time is restricted to a few city is 1.5-3 tons. The chief criterion, breathing apparatus into a rubber tube hours (usually 3-4) per day. Weather besides adequate carrying capacity, ap- attached to the ring. This causes the ring conditions and other factors further limit pears to be speed, which is important to rise, and the bag is maintained at a a diver's fishing time to around 80 days because some of the fishing grounds are convenient height, anchored by the per year. Although most divers make a considerable distance from port. Most weight of the sea urchins. As the bag is daily fishing trips, some with large sea urchin boats can cruise at IS-20 filled with more sea urchins, additional vessels make 2-day trips. On these oc- knots. In the past, vessels with large air is put into the tube to increase the casions, collected sea urchins are kept capacity, such as albacore trollers, were height of the bag. When the collecting in mesh bags underwater in sheltered used as carriers for transporting sea ur- bag is completely filled with 50-70 kg spots until the trip home. chins from the fishing grounds to dock- of sea urchins, the tube is filled with Divers were interviewed periodically side. Some divers operate by them- enough air to float the bag to the sur- between July 1974 and February 1975, selves, while those in larger vessels face. A line attached to the boat keeps and again in January and February 1977 usually work in pairs or threes. All the the bag from drifting away'l. This to get catch data. These divers fished at divers on a boat may be in the water at method is especially useful for single- the Channel Islands and at mainland the sime time, or one may act as a diver operations. Boats with tenders (or sites just north of Santa Barbara. Data tender, loading the catch into the boat. diver-tenders) often store collected sea thus obtained revealed that catch rates Major home ports of the sea urchin urchins in large cargo nets, which did not change significantly during the diving boats are Santa Barbara, Oxnard, facilitates unloading (Fig. 9). two periods (Table 3). Boats with a Port Hueneme, and San Pedro. All harvesting is currently done by single diver averaged around 250 Diving operations begin with prelim- hand, although an airlift system was kglhour during both periods, and diving inary searches for concentrations of sea tested by one firm, with reported suc- urchins. After finding an area with ade- cess. In our own experiments, we suc- quate numbers, the diver cracks open a cessfully pumped red sea urchins few sea urchins to check the quality of through a 25 cm hose from depths of 15 Table 3.-Comparison of catch per day by single- roe. If satisfactory, harvesting begins. m, but we found it difficult to get diver boats during two periods. Most divers have their own methods for enough force with an airlift system at July 1974- Jan - Aug. 1975 Feb 1977 collecting sea urchins. One effective shallower depths. Further, we found the Item N = 38 N =I2 method is to use a short-handled rake hose too cumbersome and impractical Average catch to dislodge sea urchins and scoop them to use in areas of dense kelp. per day (kg) 918 922 into a small collecting bag or wire cage. Average time spent -~ underwater (hours) 34 37 As this is filled, the sea urchins are "Jerome Belts, commercial sea urchin diver, Lom- Average catch per hour transferred underwater into a larger poc, Calif Personal commun. underwater (kglhour) 269 249

IO Marine Fisheries Review time averaged about 3.5 hours per day. Data from 48 deliveries made by single- diver boats (including the 38 in Table 3) and 16 deliveries by two-diver boats showed that the latter were somewhat more productive. The single-diver boats averaged 986 kglday while the two-diver boats averaged 2,258 kgid (or 1,129 kgidiver). In 1983 the average catch for single-diver boats was lower, probably on the order of 780-900 kgidayll. In some areas, such as near San Diego, the daily catch is usually even lower. The average depth fished during 1974-75 was 8.2 m (range 4.0-15.2 m). Most divers interviewed recently report- ed diving a bit deeper on the average. The number of boats engaged in the fishery varies considerably by year. During the peak year of 1981, 271 boats reported sea urchin landings. Of these, 42 boats (15 percent) landed 56 percent Figure 9.--Sea urchins retained in cargo nets on dive boats are easily and quickly of the total catch, and 85 boats landed unloaded into trucks 85 percent4 In port the catch is weighed and load- ed directly into waiting trucks which haul the sea urchins to processing plants. The unloading booms are usually equipped with scales to weigh the catch. Some divers sell their catch through a “middleman” who handles unloading and transport, as well as market orders and dispatching boats. The average size of red sea urchins changes with harvesting intensity, be- coming progressively smaller with time. At times, however, the size increases (Fig. 10, Santa Rosa and Santa Cruz) rather than declining. This can probably be explained by the movement of divers I 1 I I I I I 1 into deeper waters as the number of *UP SOP Ocl Nor htc Jan Feb Mar

~ large sea urchins decreases in shallower ______- 1974 pi--- ~ 1975 ~ depths. Thus, a longer sampling period would probably have shown a second Figure 10 -Mean test diameter of red sea urchins taken by the commercial fishery at the northern Channel Ialands decrease in the size of the sea urchins in 1974-75. harvested from the same area, as in- dicated by the San Miguel Island sea ur- chins (Fig. IO). The mean test diameter of red sea ur- chins sampled from the commercial landings at Santa Barbara from July 1974 plant in October 1983 averaged 8/ mm. urchin fishing permit is also now re- to February 1975 was 108 mm (95 per- All processors interviewed at that time quired under a State law enacted in cent measured 102-114 mm and 99 per- agree that the size has decreased con- 1984. All vessels used in commercial cent measured 100-116 mm). Recently, siderably. fishing operations require a certificate however, the average size has been con- Those wishing to harvest sea urchins of boat registration ($125). These fees siderably lower; the diameter of 27 red in California must obtain a commercial are assessed each license year (1 sea urchins measured at a processing fishing license ($40). A revocable sea April-31 March).

47(3), 1985 Figure 11.-Flow diagram of sea urchin pro- Figure 12.-Some tools of the trade: Stackable plastic strainer for clean- cessing steps. Frozen roe is treated similarly ing roe, metal shell-cracking device, wood tray for packing roe. to fresh roe

Processing Sea urchin processing has not changed appreciably since the earlier report of Kat0 (1972). Because the prod- uct is now primarily sold fresh rather than frozen, however, packing methods are different, and a chemical treatment is used to improve the appearance of the roe. Only a small amount of roe is salted, steamed, baked, or frozen. Sea urchins delivered to processing plants in the evening are kept overnight. During warm weather, sea urchins must be stored in refrigerated rooms. Sea ur- chins kept at 2°C for 1.5 days stay alive, but the roe is noticeably softer and darker (Kramer and Nordin, ImS). Pro- cessing consists of several steps which readily lend themselves to an assembly- line operation (Fig. 11). The test is split with a cleaver or a special tool (Fig. 12). The instrument's tip is forcibly inserted into the top of the shell, which is Figure 13.--Sea urchin roe becomes firm when soaked in a saltwater solution containing alum. cracked open when the handles are squeezed, forcing the flat blades out- ward. The roe is removed with a spoon and placed in plastic strainers, then rinsed in cold saltwater to remove the type of product. The Japanese name A) The roe is placed in stackable viscera and extraneous matter. Final is given for each of the products plastic strainers. cleaning of attached membranes is done described here. B) The strainers are placed in tanks with tweezers or small forks. From this containing a solution of anhydrous point, processing methods depend on 1) Fresh roe (uni or nama uni): potassium alum, KAI(SO&, in cold

I2 Marine Fisheries Review Figure 14.-Roe is drained thoroughly before packing: a layer of cloth helps absorb moisture.

saltwater until the roe becomes firm (Fig. 13). Concentrations used vary from 0.4-0.7 percent, and soak times vary from 15 minutes to 1 hour. C) The roe is then drained (Fig. 14) and packed in small wood trays. At least 250 g, and up to 280 g, of roe are packed in a standard tray (Fig. 15). A medium-sized tray containing around 170 g is gaining in popularity, however. Occasionally, smaller trays Figure 15.-Wood trays, holding 100, 50, or 30 g are also used. each packed with The standard trays measure about 9 around 250 g of red cm x 16 cni x 1.3 cm deep (inside sea urchin roe.

47(3), 1985 13 layer of roe is packed in a tray. These trays normally hold about 1 kg of roe. E) The wood trays are tied in bundles of 8 to 13 trays, with a wooden cover c over the top. These are placed in a c. plastic bag and the roe is allowed to % drain further in a refrigerator. It is im- portant that the roe not be exposed to drafts while draining. F) Just prior to shipment. the trays are placed in insulated master cartons ’I (Fig. 17). each holding 50-54 trays. The bulk-pack foam trays are also stacked and placed in insulated master cartons with about 8-9 trays in each carton. Artificial coolant (common- ly called “jelly ice”) is added prior to shipment (about 1.4 kg per carton in winter and twice as much in sum- Figure 16- -Roe bulk-packed In foam trays. This roe will probably be used in mer). salted or cooked products. 2) Salted roe (shio uni): Methods of salting vary. depending on the require- ments of buyers. Generally, the steps are as follows. A) Layers of cheesecloth are placed on a wire rack. B) A layer of roe is placed on the cheesecloth and covered thoroughly with salt; about 25 percent salt to weight of roe is used. C) More layers of roe and salt are placed on the rack, sometimes with cheesecloth between layers, until the thickness reaches about 5 cm. D) The roe is allowed to drain for several hours or overnight; about 40-50 percent of moisture is removed. and salt uptake is 10-15 percent. E) The salted roe is packed in plastic- lined wooden kegs or plastic con- tainers, sometimes with the addition of 10 percent by weight of ethyl alcohol (95 percent). Recently a new type of shio uni has been produced using less salt but re- Figure 17. ---Insulated master carton used to ship sea urchin roe packed in wood quiring freezing for preservation. or ioain trays. Source of cartons: Plasti Personalities, 1214 W. 252nd St., Harbor This product apparently brings a high Cit). C.4 90710. price if good quality roe is used1*.

3) Steamed roe (mushi uni): A) Fresh roe is placed in wood or screen containers of various sizes. diincn\ions) and cost about $0.30 trays, 32 cm X 40 cm X 2 cm deep B) The containers are stacked and

ea

D) Alternatcly. the drained roe is bent cloth to prevent sliding and ‘2K Ydnagitd, California Uni Co , Lo\ Angeles. bulLpacked in larger perforated foam damaging of roe in transit. Only one Calif Personal commun

14 Murine Fisheries Review Figure 18.--Showcase in a sushi shop. A wood tray filled with red sea urchin roe is seen to the left; two pieces of “uni sushi” are on the counter on the right.

placed in a large steamer. bag, is stored in insulated master car- critical. In Japan as well as in the United C) The roe is steamed for about 30 tons in the freezer. States, most of the roe is bought by minutes; about 20-30 percent of mois- This method is used when the prod- “sushi” shops, which are Japanese sea- ture is removed during the process. uct is to be sold later as raw-thawed food restaurants specializing in fresh Some processors steam roe under sea urchin roe, and only good roe is seafood. Customers in sushi shops pressure, reducing cooking time to 15 acceptable. If the roe is destined to be usually sit at a counter in front of refrig- minutes or less. salted or processed further, second- erated showcases which contain many D) The roe is bulk-packed or packed grade roe may be used, and it is often seafoods, mostly raw, in plain view (Fig. in small wooden or plastic trays, and simply placed in plastic bags and 18). Sea urchin roe is displayed in the frozen. frozen in bulk. same wooden trays used by the pro- cessor. To maintain good appearance, 4) Baked roe (yaki uni): California firms have experimented broken pieces of roe are placed on the A) Fresh roe is placed in shallow with other processing methods in at- bottom, and only whole, firm roe is oven-proof dishes. tempts to service specialty markets. Two placed on the top layers of wood trays. B) The roe is baked in an oven at such items produced were canned roe The best size is 40-SO mm, but Califor- 190°C for 30 minutes. About 30-40 and freeze-dried roe. In addition, sea ur- nia sea urchin roe is usually larger. percent of moisture is removed in the chin roe has been used as feed for aquar- Skeins of roe are separated according to process. ium animals, particularly for sea anem- their color. Very large skeins are used C) The cooked roe is then packed in ones and other invertebrates. in other than fresh products, or broken small wooden trays (around 30 g) or The best quality roe is reserved for up into smaller pieces and packed on the in plastic imitation “scallop shells” the fresh product, which brings the best bottom of trays. Bright yellow roe was and frozen. prices. Secondary products are made historically considered the highest quali- from broken roe, or roe that is off-color, ty in Tokyo, although consumers in dif- 5) Frozen roe (reito uni): too large, or leaking fluids excessively. ferent areas of Japan often prefer bright A) Fresh roe of good quality is packed Salted roe is usually produced in the orange roe. Since the late 1970’s, orange in standard wood trays or bulk plas- summer, when the price of fresh roe is roe has equalled yellow roe in price in tic trays. low in Japan. Tokyo. B) The trays are stacked and inserted Because appearance is important to Trays used for the Japanese market in a plastic bag, then frozen at -17°C. the Japanese, who are said to “eat with were formerly imported from Japan be- C) The frozen roe. still in the plastic their eyes,” the packing process is cause only certain types of wood are ac-

47(3), 1985 15 ing recently in San Diego. Los Angeles, Oxnard, and Santa Barbara. These are likely to resume processing when con- ditions are favorable. Periodically, red sea urchins are harvested in northern California near Fort Bragg and trucked to central and southern California for processing. Several attempts have been made to process sea urchins in northern Califor- nia. but none has proved successful for a sustained period. The chief problem appears to be inclement weather during winter when the market is most favor- able. In addition to high seas, visibility is extremely poor during and after winter storms, making diving for sea ur- chins rather difficult and hazardous. ' '2 Nevertheless, some small-scale Drocess- Figure I9.-Sea urchin roe packed for the domestic retail market in an "oyster tray". ing is being carried out with sea urchins from Half Moon Bay to Fort Bragg to supply local sushi shops. Processors indicate that about 35-45 experienced workers are needed to clean ceptable. as they impart some odor or the appearance of the repacked product and pack 10 t of whole red sea urchins flavor to the roe. Now, however. a firm was good. Thc only drawback was the in wood trays in an 8-hour work day. in Los Angeles manufactures nearly all extra time and cost necded to transport When larger foam trays are used, the wood trays used by the U.S. industry". and repack the roe. Presently, fresh red same amount can be processed by 25 Sanitation is important because sea sea urchin roe is being shipped to Japan workers if the roe need not be aligned urchin roe. which is usually sold fresh primarily in wood trays, but some foam in the trays. If careful packing is re- out of thc shell. can easily pick up bac- bulk trays are also used. The product quired, however, only a slight savings terial and fungal contamination. To form is largely determined by the cur- in labor is realized. counteract bacteria. some processors rent prices of both. and. recently. roe The plants process sea urchins around use ultraviolet-treated water in all phases packed in wood trays has generally 200 days annually. In a typical opera- of processing. and disinfectants are used yielded higher profits. tion. 4 persons crack the shells open, by all to maintain a sanitary environ- For the domestic market, wood trays 12 remove the roe and do preliminary ment. Good refrigeration is also critical, and plastic "oyster" trays (Fig. 19). cleaning, 6 do the final cleaning, and 16 especially during summer. which are partitioned. have 5 or 10 pack the roe in wood trays? During Labor costs are rather high in an depressions, and hold 100 or 200 g of periods of full production, some plants operation which calls for meticulous roe. are used for sale through retail have 80 persons working 10-12 hours per cleaning, sorting. and packing. Thus markets. Nearly all sushi restaurants day. several processors turned to bulk-pack- prefer the wood trays, however. The quantity and quality of roe con- ing methods. In addition to savings in Several attempts have been made to tained in sea urchins is vital to proces- labor costs, bulk-packing also offered process sea urchins aboard vessels at sors. Quantity is by and large a seasonal lowcr costs for trays (plastic instead of sea. The principal advantages are prox- phenomenon. as the amount of roe wood), as well as lower shipping costs. imity to the sea urchin supply, access depends in part on the reproductive state because the plastic trays were consider- to clean salt water. and easy disposal of of the sea urchins. However, nutritional ably lighter, and only a few were need- waste products. Apparently the cost of state is important, and areas devoid of ed compared to wood trays. Once in maintaining crews and workers aboard preferred algae produce sea urchins with Japan, the roe is repacked in the tradi- the vessels for extended periods proved poor yield or poor color. tional wood trays and marketed through uneconomical. We were fortunate in being allowed to normal channels. In the early days of the fishery, pro- examine the production log of a south- The proximity of the markets and the cessing plants were concentrated in San- ern California processor. and we have use of experienced labor cnsured that ta Barbara, but by 1984 plants were constructed a graph (Fig. 20) of the located in Los Angeles (four). Long yield of premium roe processed in

"The onl) hnoun domestic tray maker I\ Mat- Beach (two). Ventura (one). and Oxnard 1975-76. The figure includes only roe siinioto. Inc., 411 E. 5th St . Los Angelcs. Cal~f (onc). Several plants stopped process- packed in trays for the fresh roe market.

16 Afmitic Fisheries Review Sea urchin roe for the domestic mar- ket is shipped in insulated cartons con- taining coolants similar to those used in overseas shipment. Both truck and air transport are used, depending on dis- tance. 04 The short shelf life of fresh sea ur- chin roe makes it imperative that the product be handled expeditiously. Fresh n-I I I,I I I I, I, I I I Mar Apr May Jun July Aug Sep Oct Nov Dec Jan Feb Mar AprI roe is usually shipped by air freight to 1975 I 1976 Japan within 30 hours after delivery of Figure 20.-Yield of sea urchin roe at a commercial the sea urchins at dockside by divers. processing plant. Only good quality roe sold fresh is in- Shipment timing is important because cluded in the yield. all imported food undergoes agricultural inspection and customs clearance at the receiving airport in Japan. Spot checks are also made by health officials to The production curve is similar to the wholesale fish dealers and preservers monitor levels of bacterial contamina- reproductive cycle of red sea urchins license ($65) from the Department of tion. It is best to ship sea urchins from (Fig. 4). The yield is lower because off- Fish and Game. In addition, the whole- Los Angeles on flights that depart colored roe is discarded, some roe is in- saler is responsible for keeping records around midnight, as they arrive before evitably lost during processing, and of all sea urchins purchased, and for dawn in Tokyo after 11-12 hours. Ship- cooked and salted roe are not included paying a tax of $2.87/t of whole sea ur- ments that arrive late in the day are held in the data. Further, the gonad index chins bought. over for inspection the following day. given in Figure 4 is based on drained Shipping and Marketing Shipments are not made on Fridays, weight of sea urchins, while the produc- because arrival date is Sunday in Japan, tion yield is based on total weight at Fresh roe is shipped to Japan by air or on Sundays, when most US. pro- dockside. freight, principally from Los Angeles cessors suspend operations. Roe color is exceedingly important in International Airport. A freight for- After official clearance, the roe is marketing. Clear, bright yellow or or- warder consolidates products from held overnight in refrigerators until early ange roe is best for the fresh market. As several firms to take advantage of lower the next morning when auctions are held many as eight color grades are used by bulk-rate charges for air freight. Since at the Metropolitan Central Wholesale California processors, and all dark or carriers do not use refrigerated contain- Fish Market, located in Tsukiji, Tokyo. discolored roe is discarded. For salted ers, each processor must include ade- Bulk-packed roe is trucked directly from roe, the preferred color is orange, which quate artificial coolant in individual the airport to outlying regions, par- is the color of high quality bottled salted shipping cartons. Unit cost for air ticularly to Miyagi Prefecture, about 325 roe made with Japanese sea urchins. freight depends on the quantity shipped. km from Tokyo. There the roe is re- In the California fishery we noted that Amounts under 100 kg are charged packed in standard wood trays before orange roe was exclusively from male $5.08/kg; between 100 and 200 kg, being marketed. red sea urchins while yellow roe was $4.4O/kg; 200-300 kg, $2.85/kg; and Most of the sea urchin roe produced usually found in females. Bernard (1977) over 300 kg, $2.16/kg. To this are add- in California is marketed fresh in Japan, and Kramer and Nordin (1975) found the ed handling charges of $17 to $45 per but an increasing amount of fresh roe same relationship in red sea urchins shipment, depending on the number of is being packed in wood trays for the from British Columbia, and the latter cases of roe shipped’? growing domestic sushi trade. Small found no cyclic changes in color of the Steamed roe is often air-shipped to amounts packed in plastic oyster trays roe. Dark brown roe represents gonads Japan, but it can also be frozen and sent are also sold in U.S. retail outlets. The degenerated because of starvation. by sea, as are all salted and frozen prod- total amount sold in the United States In addition to having good color and ucts. The basic shipping charge is pres- is unknown, but is thought to be on the appearance, best quality roe is firm, ently $388/t. Other charges (insurance, order of 30-40,OOO wood trays per small (less than 5 cm), and free of leak- labor, overland freight, etc.) are addi- month, which we estimate to be about ing fluids. Some processors feel that tional costs, as are surcharges for adjust- 25 percent of the average amount sent poor quality roe tends to occur in great- ments based on current fuel and cur- to Japan. er frequency in large (old) urchins, and rency rates? In Japan, fresh US. roe packed in for this reason they discourage harvest wood trays is sold primarily at the of the very large red sea urchins. I4Mr. Kagawa, “K’ Line Air Service, Inc., Redon- Tsukiji Market through auction. The roe do Beach, Calif. Personal commun. Persons in California wishing to buy I5T. Saito, Pacific Marine Products Corporation, is sold in lots (bundles) of 11-13 trays. and process sea urchins must obtain a Ventura, Calif. Personal commun. In other cities, sea urchin roe is sold

47(3), 1985 I7 !hrt)ugh auction or directly to major sity, and the Washington Department of \\.holcsalcrs. Bulk-pack fresh roe, re- Fisheries contributed materially to the pac'ked in Japan in traditional wood 700 contents, and we are grateful for their trabs. is sold in many cities through auc- time and cooperation. Useful com- tion and direct sales. Salted, steamed. 600 ments were provided by David Parker OI- baked roe is usually sold through (CDFG), who reviewed the manuscript - 500 tc iiianufdcturers that specialize fn and also provided much data on the har- u\cJ \ea urchin roe products. 0I- vesting section. Susan Smith (NMFS), L! 400 ixl American processors sell sea I- John Dixon (University of Southern roc to Japanese trading firms at y 300 California), and F. R. Bernard (Pacific price so they are not subjected LV Biological Station, Nanaimo. B.C.) also 4. to thc vagaries of auctioning. Some pro- 200 critically reviewed the manuscript, im- c'i'\wr\ sell their own products at auc- proving it considerably. Sennen Sala- !i~wthrough brokers. however. These 100 pare (NMFS) helped gather most of the rcceive about 5 percent of the statistics. and Rahel Fischer provided KC lor their services. The auc- extensive editorial and secretarial aid. called primary wholesalers, The junior author thanks Jerolyn Bleak 5 percent of the auction price MONTH and John Dixon for field assistance. We f:>, I .iiiclling the product. In addition, an Figure Il.-Average California catch. owe many thanks also to the Canadian .t customs duty of 10 percent is b) month. of red sea urchins. 1973- scientists whose research has added ed on fresh roe, and 7 percent on 83. Source: California Department of substantially to little-known aspects of Fish and Game. ' roe. These duties are paid on the the biology as well as the commercial

I . ot' !!it. bill of sale if the roe has fishery for red sea urchins. ' ilJ outright. If not, a small down demand and price are especially high ; X~Ii> required. and the balance of during the holiday season near the end Literature Cited

3 IS paid after the primary whole- of the year. Thus the average catch by Anonymous. 1Y77. Operations in San Diego Coun- -porta the selling price to the month in the California sea urchin ty. h W. J. North (principal investigator), Kelp fishery (Fig. 21) reflects the price struc- habitat impro\,enient prqject, Annu. Rep. 1974-75, p 15-29. Calif. Inst. Technol. of 1084. divers were paid about ture. But the lower catches from March Baker, S. L. !93. Growth of the red sea urchin, )O 5OO!t for red sea urchins. The through July are also related to low SrroriK?./o(.rritrotu.rfrarlciscmu (Agassiz) in prices uwally correspond to the high gonad yields after the spawning season. two natural habitats. M.S. thesis. Calif. State Uni\.. San Diego, 83 p. di'ii~m~!in winter. low yield during Processors in the United States some- Bennett. J.. and A. C. Giese. 1955. The annual ymng. anJ low demand in summer. To times sell their products to Japanese reproductive and nutritional cycles in two west- zocourage harvesting of good quality brokers at a flat annual price which re- ern sea urchins. Biol. Bull. (Woods Hole) 109: 226-237. SCJ urchins. some processors offer flects the value at both the high and low, Bernard. E R. 1977. Fishery and reproductive cy- bonuses uhcn high rce yields are demand periods. Often by agreement cle of the red sea urchin. Srrong~/ocenrrotus frciriciac.arius. in British Columbia. J. Fish. Res. BC h !c.ved the volunie is kept minimal in the spring Board Can. 34:604-610.

As mentioned, the prices paid at the and summer to avoid big losses. How- ~~ , and D. C Miller 1973. Preliminarv aui,fions in Japan are based on supply ever, the plants have to operate even diir- investigation on the red sea urchin resources of British Columbia (StronK\/ocPrrtrorua fim- and demand. Of course, quality is al- ing unprofitable periods, because of the cI.smrius. Agausiz). Fish. Res. Board Can., way of primary importance, and do- need to keep key personnel employed. Tech. Rep. 400. 37 p. uv\!iz Bernstein. B. B.. B E. Williams. and K. H. Mann. roc always brings the highest Processors and buyers sometimes 1981. The role of behavioral responses to . As the Japanese sea urchin fish- resort to freezing roe during the sum- predators in modifying urchins' (Strongdocen- c1.i i\ mainly a spring-summer fishery. mer when Japanese prices are low. The frofu.y drohachiemis) destructive grazing and seasonal patterns. Mar. Biol. 63:3749. ;ti-c generally lower during those frozen roe is held several months until Boolootian. R. A,, and A. R. Moore. 1956. Her- nron!hs because of high domestic pro- prices are better. and though premium inaphroditisni in echinoids. Biol. Bull. (Woods duction (Mottet, 1976). Around the mid- prices are never paid for frozen roe, the Hole) 11!:328-335. Breen. P. A,. and B. E. Adkins. 1976. Growth rings dle of August, seasonal monsoons profits are a bit better than selling f;esh and age in the red sea urchin, Strongylocoi- dqws fishing effort; at the same time, roe in summer. Irorus frarrriscunus. Fish. Res. Board Can., Pac. Bid. Sta., Nanaiino, B.C., Manuscr. Rep. Acknowledgments Ser 1413, 17 p

~ ~~ ~~-,and D C Miller 1978 We received help from many people Recobem rate in three exoloited sea urchin populations from lY72 to !Y?7. Can. Fish. Mar. in preparing this report. Fishermen, Serv. Pac. Biol. Sta., Resour. Serv. Branch, processors, brokers, researchers from Nanaimo. B.C., Manuscr. Rep. 1446, 27 p.

e United States and the Republic the California Department of Fish and ~~~~ ~ . D. C. Miller, and 8. E. Adkins. 1976. An examination of harvested sea urchin popula- Game (CDFG), Scripps Institution of tions in the Tofino area. Fish. Res. Board Can., exiri:itcrs ofsea urchin roe to Japan. The Oceanography. San Diego State Univer- Manuscr. Rep. Ser. 1401, 22 p.

Marine Fisheries Review Cameron. R. A,, and R. Hinegardner. 1974. Ini- Publ. Puget Sound Biol. Sta. (Seattle) 7 Technol. tiation of metamorphosis in laboratory-cultured 401-411. Moore, H. B., T. Jutare, 1. C. Bauer, and J. A. sea urchins. Biol. Bull. (Woods Hole) 146:3?5- Kato, S. 1972. Sea urchins: A new fishery develops Jones. 1963. The biology of Lytechinus varie- 342. in California. Mar. Fish. Rev. 34(9-IO): gurus. Bull. Mar. Sci. Gulf Carib. 13(1):23-53. ____ . and S. C. Schroeter. 1980. Sea ur- 23-30. Mottet, M. G. 1976. The fishery biology of sea chin recruitment: Effect of substrate selection Kramer, D. E., and D. M. A. Nordin. 1975. Phys- urchins in the family . on juvenile distribution. Mar. Ed.-Prog. Ser. ical data from a study of size, weight and gonad Wash. Dep. Fish. Tech. Rep. 20, 66 p. 2 :243-247. quality for the red sea urchin (Strongy- North, W. J. 1965. Urchin predation. In W. I. Cowen, R. K. 1983. The effect of sheephead locentrotusfmnriscanus (Agassiz)) over a one- North (principal investigator), Kelp habitat im- ( pulcher) on red sea urchin year period. Can. Fish. Mar. Serv., Vancouver provement project, Annu. Rep. for 1964-65. p. (Strongylocentrotus franciscanus) populations: Lab., Manuscr. Rep. Ser. 1372, 91 p. 57-61. Calif. Inst. Technol.

An experimental analysis. Oecologia (Berlin) ___ , and ~ . 1979. Studies on . 1974. A review of the studies sup- 58:249-255. the handling and processing of sea urchin roe. porting sea urchin control as a means of restor- Dean, T. A,, S. C. Schroeter, and D. D. Dixon. I. Fresh product. Can. Fish. Mar. Serv., Tech. ing kelp beds. In W. J. North (principal in- 1984. Effects of grazing by two species of sea Rep. 870, Vancouver, B.C., 47 p. vestigator), Kelp habitat improvement project, urchins (Strongylocentrotusfranciscanus and Lees, D. C. 1mO. The relationship between move- Annu. Rep. 1973-74. p. 95.108. Calif. Inst. Lytechinus anamesus) on recruitment and sur- ment and available food in the sea urchins Technol. vival of two species of kelp (Macrocystispyri- Strongylocentrotus franciscanus and S. pur- ___ , and J. S. Pearse. 1970. Sea urchin fera and Pterogophora californica). Mar. Biol. puratus. M.S. thesis, Calif. State Univ.. San population explosion in southern California 78:301-313. Diego, 117 p. coastal waters. Science (Wash., D.C.) 167:209. Duggins, D. 0. 1980. Kelp beds and sea otters: Leighton, D. L. 1966. Studies of food preferences Pace, D. R. 1975. Environmental control of red An experimental approach. Ecology 61(3):447- in algivorous invertebrates of southern Califor- sea urchin (Srrongylocentrotus franciscanus) 453. nia kelp beds. Pac. Sci. 20(1):104-113. vertical distribution in Barkley Sound, British

Ebert, E. E. 1968. California - census ~ . 1967. Ecological investigations of sea Columbia. Ph.D. thesis, Simon Fraser Univ., and habitat survey. Underwater Nat. 5(3): urchin populations along the Palos Verdes Burnaby, B.C., 98 p. 20-22. Deninsula. In W. J. North (orincioal investiea- Paine, R. T., and R. L. Vadas. 1969. The effects Ebert, T. A. 1967. Negative growth and longevity tor). Kelp habitat improveGent pioject, Antk. of grazing by sea urchins, Srrongylocentrotus in the purple sea urchin Strongylocentroruspur- Rep. 1966-67, p. 41-54. Calif. Inst. Technol., spp., on benthic algal populations. Limnol. puratus (Stimpson). Science (Wash., D.C.) I57 Pasadena. Oceanogr. 14(5):710-719. 557-558. ~___. 1971. Grazing activities of benthic in- Palmisano, 1. F. 1975. Sea otter predation: Its role ___ . 1968. Growth rates of the sea urchin vertebrates in southern California kelp beds. In in rocky intertidal community structure at Am- Strongylocentrorus purpuratus related to food W. J. North (editor), The biology of giant kelp chitka and other Aleutian Islands. Ph.D. thesis, availability and spine abrasion. Ecology 49: beds (Macrocystis) in California, p. 421-453. Univ. Wash., Seattle, 193 p. 1075-1091. Beiheptezur Nova Hedwigia 32, Verlag von 1. Pearse, J. S., M. E. Clark. D. L. Leighton, C.

~ . 1983. Recruitment in . Cramer, Lehre, Ger. T. Mitchell, and W. J. North. 1970. Marine In M. Jangoux and J. M. Lawrence (editors), ____, L. G. Jones, and W. J. North. 1966. waste disposal and sea urchin ecology. In W. Studies I, p. 169-203. A. A. Ecological relationships between giant kelp and J. North (principal investigator), Kelp habitat Balkeema, Rotterdam. sea urchins in southern California. In E. G. improvement project, Annu. Rep. 1969-70, p. Fawcett, M. H. 1984. Local and latitudinal varia- Young (editor), Proc. 5th Int. Seaweed Symp., 1-93. Calif. Inst. Technol. tion in an herbivorous marine snail. Ecology Halifax (Aug. 25-28), p. 141-153. Pergamon ~.-,and A. H. Hines. 1979. Expansion 65(4):1214-1230. Press, Oxford, Engl. of a central California following the Feder, H. M., C. H. Turner, and C. Limbaugh. Low, C. J. 1975. The effect of grouping of Strongy- mass mortality of sea urchins. Mar. Biol. 51: 1974. Observations on fishes associated with locentrotus franciscanus, the giant red sea ur- 83-91. kelp beds in southern California. Calif. Dep. chin, on its population biology. Ph.D. thesis, ___ , and V. B. Pew. 1975. Growth zones Fish Game, Fish Bull. 160, 144 p. Univ. British Columbia, Vancouver, 126 p. in the echinoid skeleton. Am. hl.I5:731-763. Frank, P. W. 1975. Latitudinal variation in the life Lowry, L. F., and J. S. Pearse. 1973. Abalones and Quast, J. C. 1968. Observations on the food of the history features of the black turban snail Tegula sea urchins in an area inhabited by sea otters. kelp-bed fishes. Calif. Dep. Fish Game, Fish funebralis (Prosobranchia: Trochidae). Mar. Mar. Biol. 23(3):213-219. Bull. 139:109-142. Biol. 31:181-192. McCauley, J. E., and A. G. Carey, Jr. 1967. Echi- Rosenthal, R. J., and J. R. Chess. 1972. A preda- Giese, A. C., L. Greenfield, H. Huang, A. Far- noidea of Orenon. 1. Fish. Res. Board Can. tor-prey relationship between the leather star, manfarmaian, R. Boolootian, and R. Lasker. 24(6):1365-1401. Dermasterias imbricata, and the purple urchin, 1958. Organic productivity in the reproductive MacGinitie, G. E., and N. MacGinitie. 1968. Nat- Strongylocentrotus purpuratus. Fish. Bull. cycle of the purple sea urchin. Biol. Bull. ural history of marine animals. McGraw-Hill, (U. S.) 70(1):205-216. (Woods Hole) 116(1):49-58. New York; 473 p. ___, W. D. Clark, and P. K. Dayton. Greenfield, L., A. C. Giese, A. Farmanfarmaian, McLean, J. H. 1962. Sublittoral ecology of kelp 1974. Ecology and natural history of a stand of and R. A. Boolootian. 1958. Cyclic biochemical beds of the open coast area nea; Carmel, giant kelp, Macrocystis pyrifera, off Del Mar, changes in several echinoderms. J. Exp. Zool. California. Biol. Bull. (Woods Hole) l22:94- California. Fish. Bull. (U.S.) R(3):670-684. 139(3):507-524. 114. Russo, A. R. 1979. Dispersion and food differences Harrold, C., and D. Reed. In press. Food avail- Malagrino Lumare, G. 1972. Extraccion y preser- between two populations of the sea urchin ability, sea urchin grazing, and kelp forest com- vacion de las gonadas de erizo. M.S. thesis, Strongylocentrotusfranciscanus. J. Biogeogr. munity structure. Ecology. Universidad Autonoma de Baja California, 6:407-414. Higashi, H., R. Kikuchi, and K. Tabei. 1959. Escuela Superio? de Ciencias Marinas, Schroeter, S. C. 1978. Experimental studies of Nutritive elements in salted marine appetizers. Ensenada, Mexico, 79 p. competition as a factor affecting the distribu- Nutrition and Foods 11(6):62-65. Tokyo. (in Mattison, J. E., and J. D. Trent, A. L. Shanks, tion and abundance of purple sea urchins, Jpn.) T. B. Akin, and J. S. Pearse. 1977. Movement Srrongylocentrotus purpuratus (Stimpson). ~, T. Yamakawa, M. Yanise, T. Kinu- and feeding activity of red sea urchins (Stron- Ph.D. thesis, U~iv.Calif. Santa Barbara, 184 p. maki, Y. Shimizu, K. Sugii, and H. Iida. 1965. -.avlocentrotus franciscanus) adiacent to a kelp _____ , J. D. Dixon, and J. Kastendick. 1983.

Vitamins in salted sea urchin gonad. Nutrition forest. Mar. Biol. 39:25-30. ~ Effects of the starfish, fatiria miniata, on the and Foods 18(2):66-69.Tokyo. (In Jpn.) Miller, R. J., and K. H. kiann. 1973. Ecological distribution of the sea urchin Lytechinus am- Hinegardner, R. T. 1969. Growth and development energetics of the seaweed zone in a marine bay mesus in a southern Californian kelp forest. of the laboratory cultured sea urchin. Biol. Bull. on the Atlantic coast of Canada. 111. Energy Oecologia (Berlin) 56:141-147. (Woods Hole) lP465-475. transformation by sea urchins. Mar. Biol. 18: Sheer, B. T. 1945. The development of marine

~ . 1975. Morphology and genetics of 99-114. fouling communities. Biol. Bull. (woods Hole) sea urchin development. Am. Zoo]. I5:679689. Mitchell, C. T., L. G. Jones, and W. J. North. 89:103-121. Jensen, M. I., 1969. Age determination of echi- 1969. Studies on urchin larvae and recrukment Shelton, D. B., P. A. Bemal, and J. A. McGowan. noids. Sarsia P41-44. of juveniles. In W. J. North (principal in- 1982. Large-scale interannual physical and Johnson, M. W., 1930. Notes on the larval devel- vestigator), Kelp habitat improvement project, biological interactions in the California Cur- opment of Strongylocentrotus franciscanus. Annu. Rep. 1968-69, p. 106-115. Calif. Inst. rent. J. Mar. Res. 40:1095-1125.

47(3), 1985 19 Shepherd, S. A. 1973. Competition between sea nia kelp beds. In J. D. Pringle, G. J. Sharp, and Lawrence (editor). Int. Echinoderms Conf., urchins and abalone. Austral. Fish. 32(6):4-7. J. E Caddy (editors), Proceedings of the work- Tampa Bay. A. A. Balkema, Rotterdam. Silver, G. R.. and A. Brienon. 1974. Some in- shop on the relation between sea ukhin grazing , and . 1983. Spiny lob- dicators which suggest that vertical movement and commercial plantianimal harvesting. Can. sters and sea urchins: Analysis of a predator- does not occur in Strongylocentrotus fiancis- Tech. Rep. Fish. Aquat. Sci. 954:125-143. prey interaction. J. Exp. Mar. Bid. Ecol. 73:

canus (Agassiz). Lambda 1:15-18. ~ , and P. K. Dayton. 1977. Sea urchin 125.150. Southward, A,. and E. Southward. 1975. En- recruitment patterns and implications of com- Vadas, R. L. 1968. The ecology of Agarurn and dangered urchins. New Sci. 10 April l975:%72. mercial fishing. Science (Wash., D.C.) 196: the kelp bed community. Ph.D. thesis, Univ. State Water Quality Control Board. 1964. An in- 324-326. Wash., Seattle, 280 p.

vestigation of the effects of discharged wastes ~ ~, and . 1981. Population ~ . 1977. Preferential feeding: An opti- on kelp. State Water Qual. Control Board, structure, recruitment and mortality of two sea mization strategy in sea urchins. Ecol. Monogr. Sacramento, Calif., hbl. 26, 124 p. urchins (Strongyiocentrotusfranciscanus and 47: 337-371. Swan, E. F. 1961. Some observations on the S. purpuratus) in a kelp forest near San Diego, Wilson, K. C., P. L. Haaker, and D. A. Hanan. growth rate of sea urchins in the Stron- California. Mar. Ecol. Progr. Ser. 5:255-268, 1978. Kelp restoration in southern California. gylocentrotus. Biol. Bull. (Woods Hole) 120: Fed. Rep. Germany. fn R. Krauss (editor), The marine plant bio-

420-427. ~ , and L. A. Levin. 1982. Do sea ur- mass of the pdcific Northwest coast, p. 183-202. Tegner, M. 1. 1980. Multispecies considerations chins and abalones compete in California kelp Pac. Northw. Reg. Comm., Oreg. State Univ. of resource management in southern Califor- forest communities?, p. 265.271. In J. M. Press.

20 Marine Fisheries Review