Abstract
Shoots and clumps of shoots of the commercial brown seaweed Ascophyllum nodosum (“rockweed”) add to the benthic complexity of the intertidal environment, providing an important habitat for invertebrates and vertebrates. To protect the structure of this habitat, management plans for the rockweed harvest of southern New Brunswick include restrictions on gear type and exploitation rates limited to 17% of the harvestable biomass. However, owing to physical and environmental factors, the harvest is not homogeneous, creating patches of exploitation ranging from 15 to 50%.
A direct relationship existed between clump vulnerability, weight and length in a controlled harvest at 50% exploitation within 8m by 8m plots. At this exploitation rate, the gear rarely impacted clumps below 50 g or 60 cm in length. Clumps larger than 300 g and 130 cm were reduced by up to 55% of their length and 78% of their biomass. The overall impacts of the harvest on intertidal habitat is however of short duration as biomass recovers after a year of the experimental harvest. The rapid recovery is mostly due to a stimulation of growth and branching of the suppressed shoots of the clumps. Some harvested plots showed biomass even higher than initial levels, suggesting an increase in productivity at least during the first year after the harvest.
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References
Aberg P (1990) Measuring size and choosing category size for a transition matrix study of the seaweed Ascophyllum nodosum. Mar. Ecol. Prog. Ser. 63: 281–287.
Ang PO, Sharp GJ, Semple RE (1993) Changes in the population structure of Ascophyllum nodosum (L.) Le Jolis due to mechanical harvesting. Hydrobiologia 260: 321–326.
Cousens R (1984) Estimation of annual production by the intertidal brown alga Ascophyllum nodosum (L.) Le Jolis. Bot. Mar. 27: 217–227.
DFO (1999) The impact of rockweed harvest on the habitat of southwest New Brunswick. DFO Maritimes Regional Habitat Status Report 99/2E: 1–9.
Gee JM, Warwick RM (1994) Metazoan community structure in relation to the fractal dimensions of marine macroalgae. Mar. Ecol. Prog. Ser. 103: 141–150.
Hamilton DJ (2001) Feeding behavior of common eider ducklings in relation to availability of rockweed habitat and duckling age. Waterbirds 24: 233–241.
Hicks GRF (1980) Structure of phytal harpacticoid copepod assemblages and the influence of habitat complexity and turbidity. J. Exp. Mar. Biol. Ecol. 44: 157–192.
Johnson SC, Scheibling RE (1987) Structure and dynamics of epifaunal assemblages on intertidal macroalgae Ascophyllum nodosum and Fucus vesiculosus in Nova Scotia, Canada. Mar. Ecol. Prog. Ser. 37: 209–227.
Lazo L, Chapman ARO (1996) Effects of harvesting on Ascophyllum nodosum (L.) Le Jol. (Fucales, Phaeophyta): A demographic approach. J. Appl. Phycol. 8: 87–103.
Masterson J (1998) Investigation of the effects of macrophyte structure, food resources and health on habitat selection and refuge value in vegetated aquatic systems. Dissertation Abstracts International Part B: Science and Engineering 58: 4019.
Pavia H, Carr H, Aberg P (1999) Habitat and feeding preferences of crustacean mesoherbivores inhabiting the brown seaweed Ascophyllum nodosum (L.) Le Jol. and its epiphytic macroalgae. J. Exp. Mar. Biol. Ecol. 236: 15–32.
Rangeley RW, Kramer DL (1998) Density-dependent antipredator tactics and habitat selection in juvenile pollock. Ecology 79: 943–952.
Sharp GJ (1986) Ascophyllum nodosum and its harvesting in Eastern Canada. In: Case studies of seven commercial seaweed resources. FAO Technical Report 281:3–46.
Sharp GJ, Ang PO, McKinnon D (1995) Rockweed harvesting in Nova Scotia, Canada: Its socio-economic and biological implications for coastal zone management. In Wells PG, Ricketts P (eds), Proceedings of the Coastal Zone Conference: 1632–1644.
Sharp GJ, Tremblay DM (1985) A tagging technique for small macrophytes. Bot. Mar. 28: 549–551.
Ugarte R, Sharp GJ (2001) A new approach to seaweed management in eastern Canada: The case of Ascophyllum nodosum. Cah. Biol. Mar. 42: 63–70.
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Ugarte, R.A., Sharp, G., Moore, B. (2006). Changes in the brown seaweed Ascophyllum nodosum (L.) Le Jol. plant morphology and biomass produced by cutter rake harvests in southern New Brunswick, Canada. In: Anderson, R., Brodie, J., Onsøyen, E., Critchley, A.T. (eds) Eighteenth International Seaweed Symposium. Developments in Applied Phycology, vol 1. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-5670-3_16
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DOI: https://doi.org/10.1007/978-1-4020-5670-3_16
Publisher Name: Springer, Dordrecht
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