History of British animals - University of Guam Marine Laboratory

FISHES. 221In the preceding enumeration of British Fishes, I have taken notice ofa few species which seem entitled only to the rank of stragglers, such as theFlying Fish, Remora, and a few others. The geographical distribution ofthese speciesis so far ascertained, that individuals occurring in particularplaces may, with some confidence, be regarded as having strayed from theirordinary haunts, and not likely either to remain permanently, or to multiply.But there are a few species,in the genera Wrasse and Gurnard, forexample, which, though they have been seldom observed on our coasts, arestill permitted to occupy a place in the British Fauna. The geographicaldistribution of these species is too little known to permit any accurate opinionbeing formed respecting their ordinary haunts. They may, probably,be found more frequently in our seas, as the products of our fishing boats areexamined with more attention. In this department there is much which hasbeen neglected,so that a rich harvest of discovery still awaits the zealous andpractical cultivators of the science of Ichthyology who have access to extensivefishingstations.The revolutions which have taken place in the different epochs of the earth'sduration, and which have left memorials of their influence, in the numerousrelics of extinct species which the different strata contain, have extendedtheir destructive operations to fishes ; an occurrence attested by the remainsof teeth and vertebra?, and entire impressions of fish, exhibited by many strata.But those parts which have been preserved, exhibit so imperfectly thecharacteristic mark of the species, as to render it difficult, if not impossible,in the present state of ichthyological osteology, to give notices of their historyat all calculated to interest the reader.The circumstances which regulate the physical distribution of Fishes, appearas yet to be imperfectly determined. Living in a medium, less influencedby changes of temperature than the atmosphere, the mere action of heatexercises but little control. Yet it is probable that the attachment of thePilchard to Cornwall and the Tusk to Zetland, may arise from this ciixumstance.Fish appear, however, to have peculiar local attachments, frequentingcertain banks, shores, or tideways, in preference to others. Thus, theHake and the Braize, while they are distributed along the south-westernshores of England, and the coast of Ireland, are likewise extended, though lessabundantly, to the Hebrides, while their northern limits on the east coastare much more circumscribed. Suitable food is probably the great regulatorof these distributions.The migrations of fishes, in compliance with the arrangements of theirreproductive system, exhibit the most singular movements, often complex,but always useful to man. Those which inhabit the inaccessible depthso'fthe sea, in ordinary cases, approach the shores, towards the season of spawning; and, after depositing their eggs in suitable situations, again retire totheir inaccessible haunts. The fry occupy for a time their littoral birthplace,and then follow the course of the older individuals, though in severalcases the young seem to execute movements different from the full grownfish. Not a few species, as the salmon, which have their ordinary residencein the sea, approach, towards the spawning season, the shores, enter estuariesand ascend rivers, where, having selected a suitable place, they depositetheir eggs, and again return to the sea. The fry, after a certain period, likewiseleave the fresh waters and betake themselves to the sea. Similar movementsare executed by the fish which inhabits lakes. As the spawningson sea-approaches, several species, as the Gwiniad, leave the deep water, andapproach the margin while ; others, as the Roach, not onlv approach themargin of the lake, but ascend the neighbouring streams.—With a few otherspecies, as the Eel, for example, these movements are reversed the ; spawningfish leave the fresh-water lakes and rivers, and retire to the sea to