Spawning behaviour

There is concern that oil spills could disrupt the spawning behaviour of anadro-mous species, such as salmon, that live their adult lives in salt water but return to fresh water streams to spawn. Tests have shown that, while salmon will sometimes avoid oil on open water, the exposure to oil may not badly disrupt their homing instinct as they tend to continue on to their freshwater home streams. Experience in actual spills has not been recorded. 

Newcombe, C. and Hartman, G., 1973. Some chemical signals in the spawning behaviour of rainbow trout Salmo gairdneri). J. Fish Res. Board. Can., 30 995—997. 

Olsen KH, Liley NR (1993) The significance of olfaction and social cues in milt availability, sexual hormone status and spawning behaviour of male rainbow trout (Oncorhynchus mykiss). Gen Comp Endocrinol 89 107-118... 

Olsen KH, Jarvi T, Mayer I, Petterson E, Kroon F (1998) Spawning behaviour and sex hormone levels in adult and precocious brown trout (Salmo trutta L.) males and the effect of anosmia. Chemoecology 8 9-17... 

Smith, R.J.F. 1976a. Seasonal loss of alarm substance cells in North American Cyprinoid Fishes and its relation to abrasive spawning behaviour. Can. J. Zool., 54, 1172—1182. 

That wild yellowfin tuna spawn naturally in captivity demonstrates that no such cues are missing for this species and suggests that perhaps the missing cues in bluefin may be related to the long migrations that are associated with their spawning behaviour and/or the deep diving that occurs in nature and that cannot be mimicked in captivity (Rooker et /., 2007). 

Fish appear to be more sensitive to organic mercury compounds than to inorganic compounds, both lethal and sub-lethal effects being reported at exposure levels of 1.0 /Ag/L. The spawning behaviour of the minnow Pimephales promelas was inhibited by exposure for 42 days to 0.1 /Ag/L of methyl mercuric chloride, and at 0.2 ftg/L 90% died during the test period no effects were noted at exposures of 0.07 ftg/L (Mount 1974). 

Chien, A. K. (1973). Reproductive behavior of the angelfish Pterophyllum scalare (Pisces Cichlidae) II. Influence of male stimuli upon the spawning rate of females. Animal Behaviour 21,457-463. 

De Fraipont, M. and Sorensen, P. W. (1993). Exposure to the pheromone 17cc,20 /3-dihydroxy-4-pregnen-3-one enhances the behavioral spawning success, sperm production and sperm motility of male golddsh. Animal Behaviour 46,245-256. 

All the above remarks about behaviour apply to distribution. Locomotion whilst on the winter ground, run of the migrating stock, spawning dispersion, gathering into the feeding or migrating shoal - each of these characteristics of distribution is closely associated with the metabolic pattern of the population. 

Pickett JA, Griffiths DC (1980) Composition of aphid alarm pheromones. J Chem Ecol 6 349-360 Ram JL, Mueller CT, Beckmann M, Hardege JD (1999) The spawning pheromone cysteine-glutathione disulfide ( Nereithione ) arouses a multicomponent nuptial behaviour and electro-... 

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