Sea-Temperature, Breeding and Distribution in Marine Animals

Abstract

Breeding in marine animals has long been recognised in a vague way as being in some degree dependent upon sea-temperature. This attitude is well shown in Lo Bianco's last valuable contribution to our knowledge of the breeding periods of practically the whole fauna of the Gulf of Naples. In the Introduction to this work Lo Bianco (1, p. 531) gives tables of temperature observations for a number of years, but does not attempt to correlate them with the breeding periods observed. There are in the literature some observations of reproduction in particular animals being dependent upon particular temperatures, notably by Schmidt (2); but no attempt has been made, so far as I know, to show in a general way the connexion between breeding and temperature in marine animals. It is clear, however, from the writings of Appellöf that this naturalist had anticipated in his mind some of the results obtained from the experimental observations described briefly in the following pages and of the deductions made therefrom. It is believed that these experimental observations have afforded a clue which gives an insight into the way in which breeding may be correlated with temperature in a large number of marine animals, but owing to the inadequacies of breeding records and of observations on physical conditions in the sea only a brief survey has been attempted here, and a fuller discussion of the phenomena is reserved for a later work. In the following pages the extrusion of ripe ova, or the fertilisability of eggs with subsequent development, is taken as the criterion of breeding.

The recent arrival of the oceanic isopodIdotea metallica Bosc off Helgoland (German Bight, North Sea): an indication of a warming trend in the North Sea?

“…Parameters connected with environmental temperature are among the most important physical variables controlling the large-scale distributions and the abundances of marine organisms, though it is often not clear what aspects of temperature are the crucial limiting conditions and what their exact mode of action is (Orton, 1920;Hengeveld, 1990;Bhaud et al, 1995). It is not surprising, thus, that in most scenarios the predicted climate change will have profound implications for ecological conditions (e.g.…”

The reproductive biology of the baby clam, Marcia opima, from two geographically separated areas of India

“…Temperature has been cited as the major environmental factor regulating reproduction in marine bivalves (Sastry, 1979). It has been suggested that the breeding period of a species occurs at characteristic temperatures, which remain a constant throughout the geographical range (Orton, 1920). Gametogenesis is initiated and spawning occurs only within fairly narrow, species-specific temperature ranges.…”

“…Studies have shown that gametogenic cycles in marine invertebrates are influenced by exogenous factors (Giese, 1959;Fretter and Graham, 1964;Wilson, 1969;Sastry, 1970Sastry, , 1979Adiyodi and Adiyodi, 1983), of which temperature is believed to be one of the most significant (Orton, 1920;Mann, 1979). Temperature is influential on the onset of both gametogenesis and spawning in many clam species (Calabrese, 1970;Keck et al, 1975;Hesselman et al, 1989;Kanti et al, 1993;Lubet, 1994).…”

The Breeding of Arenicola Ecaudata Johnston and A. Branchialis Aud. & Edw. at Plymouth

“…The breeding cycles of animals and plants are usually dependent in some way on annual fluctuations in external conditions, particularly temperature and food supply (Orton, 1920;Thorson, 1946;Qasim, 1956;Crisp & Southward, 1958). At Plymouth the same temperature regime is experienced by both A. ecaudata and A. branchialis and the same food supply is available to each.…”

“…According to Orton (1920), cosmopolitan species should have a wide range of temperature within which breeding can occur; cold-water species near their warmer limits should breed in the colder months of the year; warm-water species near their colder limits should breed in the warmer months of the year. Many organisms have been shown to conform to these conditions, but the two ecaudate species of Arenicola do not.…”