The ecology of eelgrass meadows in the Pacific Northwest: A ...

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1978, for all assumptions, formulations, and consideratlotls used in the calculations) . If these calculations are even only approxiruately correct, the economic value of seagrasses 1s enorlnous in the Pacific Horthwest. Proctor et al. (198db) calculatcxi that ttlere are 8,4dd ha (21,WW acres) of eelyrass ln Washington (this probably does not include Puget Sound), L,OW ha (5,c)W3 acres) In Oregon, and 1,odW ha (4,LWU acres) In northern California. On a prslstent annual basis this represents a sizeable econcmic resource, even without considering coastdl-sediment stabilization value, wlilch is ~ncalculable. Specifically in the Northwest there are some data that relate to economlc values of food anlmals associated with eelgrass. hebb and Iiourston (1979) fou:lu thdt in southern Brltlsh Colur~ibla alorie, the value of the Pacific herrlrig fishery for 1976-77 was $29.9 million (81,000 tons, $29 million for roe; 7,000 tons, $0.9 million tor food fish). Helfferich and WFOy (1978) reported that the total 1976 catch of Pacific herring (20.2 million tons) was worth $10.7 million. It must be remembered that herring lay eggs on algae, pilings, and several types of hard substrates as well. Dr. Robert Trulnble, bJashinyton State Department of Fisheries, related the values of the Pacific nerring in \.Jashinyton State for 1979-8k9 (Table lb). The co~i~bined value for 1979 was $4,46d,122. In 19t3W the combined value was Y1,774,b70. 111 lYitl the sport bait price was $2).33-$~.4~/lb; canmercial bit was $d.lU/lb. This price was lower due to low crab stocks for which the comn~ercial bait was sold. The last liarvest of roe herring was iri 19819, owing to iow ppulatlons in Washlryton State. In Iiashlngton Stdte there are no records kept on trie fcucl fishery of tleLrlng, since the food use 1s locallzed. Eelgrass is the .adlor substrate for egg deposltlorl, but the herring also use algae. The largest sinyle ppuldtlon of herrlry is in the Strait of Gmryla. Large populations are also founu at Port Orchdru, Port Maaison, Quartermaster Harbor, southern Hood Canal, Discovery Bay, Port Gamble, and lesser populations in the San Juan Islands, in Wastlinyton State (Dr. Robert 'rumble, pers. colnm. 1982). erring lay eggs on eelgrass in February-March in Washington State and in mid-April to mid- Flay in the Strait of Georgla. Dr. Lynn Goodwin, 'CJashlngton State Deprtment of Flsherles, applied the data on values of shellfish in Washington State (Table 161 (pers. cam. 1982). Eelgrass provides the cover for the juvenile spot shrlnip to mature. Thls resource is primarily taken in Hood Canal. Dr. Ken Chew, University of Washington (pcrs. cwinm.) provided the current (1932) values ot several of the shellfish spies (Table 16). Dr. Baumgartner, Washington stace Department of ~isheries, related the harvest and price values for Dungeness crabs caught in Puget Sound and the coastal harvest. The number of crabs actually taken in eelgrass cannot be ascertained, since the crabs range from depths of 6 m (28 ft) to 72 m (240 ft). It is known that the crabs use eelgrass at certain times in their life cycle: in the juvenile stage, during spring molting, and at certain times of molting throughout the year. But the exact extent they depend on eelgrass or the exact role of eelgrass in their existence are yet to be discovered (pers. ccmm. 19821. The Washington State Department of Game estimated the economic value to the State of Washington for black brant. In the 1981-82 season, each bird taken by hunting was worth $50 to $60/bird and $lOO/man/day. In the 1981-82 season there were 1,500 brant taken during the hunting season. Finally, Stokes (1978) estimated the value of the various animal species which result in indirect or direct income to the State of Washington. It appears that income generated by the estuarine habitats and wetlands of the State comes to millions of dollars. Only those species listed by the Washington State Department of Fisheries are given in Table 16. The prices are based on 1975 values. Stokes (1978) listed the commercial, recreational, and 67
Table 16. Harvests and value of ~CnXIErcially important animals frm eelgrass, Washington State (Personnel, Washington State Department of Fisheries; Stokes 1978 ). Spec ies Year Amount of harvest kg (lbs) Value in $ (U.S.) Pacific herring me Sport bait Cmnerc ial bait Fae Sport bait Umnerc ial bait Spot prawn ( Pandalus platyceros Oannerc ial harvest $2.69/1b; Stokes (1978; 1975 prices) Sport harvest Hard shell clams Carmerc ial harvest (wet wt) Butter clams $O.lO/lb; Stokes (1978; 1975 prices) Horse clans $0.17/lb; (1978; 1975 prices) -- -- $0.25 to 0.30 each; $0.17/lb; Stokes (1978; 1975 prices) -- Native little necks $1.10 to 1.20/lb; $0. 21/lb; Stokes (1978; 1975 prices) -- Manila continued
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~~~/0~-84/24 September 1984 THE ECO
Page 4 and 5:
PREFACE Nearly half the population
Page 6 and 7:
CONTENTS PREFACE ..................
Page 8 and 9:
FIGURES Number 1 2 ................
Page 10 and 11:
ACKNOWLEDGMENTS I wish to acknowled
Page 12 and 13:
Because eelgrass is a rooted plant,
Page 14 and 15:
CHAPTER 1 THE PHYSIOGRAPHIC SETTING
Page 16 and 17:
Table 1. Precipitation, temperature
Page 18 and 19:
Table 2. Distribution and extent of
Page 20 and 21:
Table 2. (Concluded) Extent of mat
Page 22 and 23:
CHAPTER 2 THE BIOLOGY OF EELGRASS 2
Page 24 and 25:
Table 4. Field observations on eelg
Page 26 and 27:
leaves overtopped them and created
Page 28 and 29:
1.0- influence the redox potential
Page 30 and 31: Oxygen There are Little data to ind
Page 32 and 33: enough, increased erosion of bottom
Page 34 and 35: The terms used to describe biomass
Page 36 and 37: estimates are reported on work done
Page 38 and 39: Figure 10. Eelgrass at Blakely Isla
Page 40 and 41: increase in p~), and the sediments
Page 42 and 43: particulate matter and DOM were hig
Page 44 and 45: Table 9. Nutrient content of eelgra
Page 46 and 47: ecause it is dominated by a single
Page 48 and 49: epibenthos, and other components al
Page 50 and 51: shorebirds). From a recent thorough
Page 52 and 53: pink shrimp, and bottom fish (Proct
Page 54 and 55: Table 13 a. (Continued) Phyltnn, cl
Page 56 and 57: Phylum, class, and Resident or Livi
Page 58 and 59: Table 13b. (concluded) Resident or
Page 60 and 61: Table 13c. (Concluded) Living Feedi
Page 62 and 63: eelgrass) , while 29 species were f
Page 64 and 65: (239,d9~,9(ii9 kg) (outram and Huln
Page 66 and 67: Washington State Game Dept., pers.
Page 68 and 69: Table 15. Energy in various ccmpart
Page 70 and 71: Export of whole by waterfowl Figure
Page 72 and 73: storms erode and dislodge some eelg
Page 74 and 75: CHAPTER 6 HUMAN IMPACTS-MANAGEMENT
Page 76 and 77: apparent darnazje. IUllzomes and ro
Page 78 and 79: great annual range of water tempera
Page 82 and 83: Table 16. ( CDncluded) Spec ies yea
Page 84 and 85: REFERENCES Rdarns, S.M. 197va. The
Page 86 and 87: seagrass community. Pages 153-162 i
Page 88 and 89: on current flow. Estuarine Coastal
Page 90 and 91: Inst. Agric. Res., Tohoku Univ.: 13
Page 92 and 93: In flvt. seayrasses, l'halassia McR
Page 94 and 95: eelgrass (~ostera marina L. ) Phill
Page 96 and 97: along the Strait of Juan de Fuca. N
Page 98 and 99: diatom assemblages in Netarts Bay,
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