The Role of Kelp in the Marine Environment - National Parks ...

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collected off the Cumbrian coast right beside two outfalls carrying industrial wastes failed to reveal any reduction in species numbers. They state that the effluent released from the pipes are “not inimical” to a healthy biota in the receiving area. Christie et al. (2003) and Jørgensen and Christie (2003) note that the three distinctive areas of the alga, i.e., holdfast, stipe and frond, support three different faunal groupings. The three dimensional holdfast with its internal spaces provides a refuge area for mobile species of polychaetes, e.g., Anaitides, Eulalia, Harmothoe, Hediste, Kefersteinia, Lagisca, Lepidonotus, crustaceans, e.g., Bodotria, Idotea, Apherusa, Jassa, Melita, Porcellana and echinoderms e.g., Amphipholis, Asterina, Ophiothrix, Asterias, Psammechinus, Pawsonia and Ocnus while the lower part of the stipe with its well-developed epiphyte community also supports a variety of polychaetes, e.g., Amblyosyllis, Brania, Pionosyllis, Trypanosyllis crustaceans, e.g., Caprella, Pariambus Ammothelia, Anoplodactylus, molluscs e.g., Onoba, Tricolia, Elysia and echinoderms e.g., Echinus, Psammechinus, Henricia. The frond supports the lowest numbers of species while the holdfast was found to support the highest (Christie et al., op. cit.). These authors found that species abundance in the stipe was highest in Summer although there were large variations between sites and seasons from a small number of individuals to more than 80,000 per stipe. Furthermore, season or habitat volume was not related to species diversity but was related to species abundance. 3. Food & Feeding A. Invertebrates With regard to the kelp as a direct food source for invertebrates, gastropods e.g., Patella and Helicon and some echinoderms, e.g., Echinus and Psammechinus are known to browse on kelp and these same group of species will also use other algae present within the kelp forest. Indirectly (through particulate organic matter), the kelp and associated algal species contribute to the food resource of suspension and deposit feeders (Dugan et al., 2003) to feeding groups that are abundant in kelp forest, e.g., sponges, many polychaete families such as terebellids, sabellids, serpulids and spirorbids, bivalves, cirripeds, bryozoans and echinoderms such as holothurians and crinoids and tunicates. These in turn, along with the browsers (and other sources such as phyto and zooplankton), act as the food resource for predators such as the 29
cnidarians, predatory polychaetes, e.g., scale worms, syllids, hesionids, phyllodocids and nereids, isopods and the large decapods such as lobster and crab. Drift algae, including the different kelp species, are washed up on our shores mostly during the autumn and winter months but this event can occur at any time depending on when storms happen. Even before the drift weed is washed ashore, it acts as a floating refuge and dispersion method for crustaceans and juvenile fish (B. O’ Connor, pers. obs.). The contribution kelps make to this drift weed is not known but Steneck et al. (2002) quote a figure of between 60–99% from Mann (2000) for eastern Nova Scotia. As the weed rots on the shore, it provides a valuable resource of organic matter for amphipods and hypoxic/anoxic-tolerant infaunal opportunistic polychaetes such as Malacoceros and Capitella. These in turn act as a food resource for bird species such as Curlew Numenius arquata (B. O’ Connor, pers. obs.). Bustamente and Branch (1996) working on the west coast of South Africa, studied the most abundant intertidal grazers (Patella sp) and filter feeders (Mytilus, Aulacomya and Gunnarea) and investigated their connection with in situ local production and that generated from subtidal kelp forests. They found that the selected species used kelpderived detritus as their main source of organic carbon and nitrogen. They also found that more generalised intertidal grazers relied mainly on the in situ epilithic algal species and that kelp-derived detritus represented more than 65% of particulate organic matter while phytoplankton contributed only 6%. They conclude that subtidal macrophyte production greatly influences the structure of intertidal rocky shore communities on the west coast of South Africa. Soares et al. (1996), who also worked off the South African coast around Cape Agulhas found that the infaunal surf clam Donax serra was significantly negatively impacted by stranded kelp. They examined 12 beaches and found that densities of adult clams were significantly higher on beaches that had low stranded kelp cover but did note that this did not apply to juveniles. They postulate that kelp strandings interfere with Donax feeding and burrowing activities, dislodging animals of increasing size gradually downshore to the saturation and surf zones, where adult populations are eventually established. They go on to note that kelp gulls predate upon the dislodged clams. 30
Page 1: The Role of Kelp in the Marine Envi
Page 4 and 5: Details of Contributors Birds Fish
Page 6 and 7: Executive Summary Kelp forests have
Page 8 and 9: Birds Acknowledgements Professor R.
Page 10 and 11: Introduction Kelp species represent
Page 12 and 13: Each year the kelp plant renews its
Page 14 and 15: estimate (Birkett et al., 1998) of
Page 16 and 17: Other researchers have highlighted
Page 18 and 19: Figure 2 δ 13 C values from the di
Page 20 and 21: kelp population was estimated by Ar
Page 22 and 23: Figure 4 Growth in length of the la
Page 24 and 25: varies with the age of the plants.
Page 26 and 27: Table 3 Primary production as tonne
Page 28 and 29: accuracy. Most epiphytic algae are
Page 32 and 33: Lavery et al. (1999) and Dugan et a
Page 34 and 35: (op. cit.) and Lorentsen et al. (op
Page 36 and 37: Laridae (Gulls) e.g., Herring Gull
Page 38 and 39: Interesting studies of the interact
Page 40 and 41: 1985). These birds prey upon e.g. b
Page 42 and 43: as amphipods and crabs beneath. Pur
Page 44 and 45: An interesting and indirect interac
Page 46 and 47: 5-8% lower than velocities above th
Page 48 and 49: Methods of Kelp Harvesting Impact R
Page 50 and 51: Scale of kelp removal It is self ev
Page 52 and 53: Blade cutting vs. complete plant re
Page 54 and 55: � fallow years, as successfully p
Page 56 and 57: trophic and habitat associations (N
Page 58 and 59: Foreman (1984) noted that if sustai
Page 60 and 61: variability in benthic community st
Page 62 and 63: lock was occupied by laminarians an
Page 64 and 65: Laminaria hyperborea (Gunn.) Foslie
Page 66 and 67: Pylophora crispa, 1% Ceramium nodul
Page 68 and 69: Most species on L. digitata were en
Page 70 and 71: after 3 days exposure in September
Page 72 and 73: many species have planktonic larvae
Page 74 and 75: decline in juvenile rockfishe, i.e.
Page 76 and 77: Species classified as threatened or
Page 78 and 79: The conservation status of bird spe
Page 80 and 81:
Production Future Research Nearly a
Page 82 and 83:
� Biomass and standing stock surv
Page 84 and 85:
legislative obligations in relation
Page 86 and 87:
Conclusions Even well managed kelp
Page 88 and 89:
waters and with the postulated rise
Page 90 and 91:
Arzel, P. (1998). Les laminaires su
Page 92 and 93:
Bustamante, R. H. & Branch, G. M. (
Page 94 and 95:
Christie, H., Jorgensen, N.M., Nord
Page 96 and 97:
Deady, S. and Fives, J.M. (1995b).
Page 98 and 99:
ecosystems. Bulletin of Marine Scie
Page 100 and 101:
Graham, M. H. (2002). Prolonged rep
Page 102 and 103:
Kain, J. M. (1977). The Biology of
Page 104 and 105:
Mann, K. H. (1988). Production and
Page 106 and 107:
Nicholson, N.L. (1970). Field studi
Page 108 and 109:
Quast, J. C. (1968a). Fish fauna of
Page 110 and 111:
Sellers, R. M. (2004). The Great Co
Page 112 and 113:
Swaby, S.E. and Potts, G.W. (1990).
Page 114 and 115:
Went, A. E. J. (1957). List of Iris
Page 116 and 117:
Appendix 2 Macroinvertebrate specie
Page 118 and 119:
Gibbula umbilicalis Helcion pelluci
Page 120 and 121:
Appendix 3 Description of habitat,
Page 122 and 123:
Appendix 3 continued Anguilla angui
Page 124:
Appendix 4 Conservation status of b
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