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J. A. RITCHING AND F. J. EBLING
I. INTRODUCTION
The object of our work has been to find out how the distribution of
marine organisms in a limited coastal area is determined, how they
react with each other and with their inanimate environment, and how
their numbers are controlled. Our studies involve the assessment of
physical and chemical conditions of the environment, observations of
distribution and abundance of plants and animals, field experiments in
which we interfere either with the inanimate environment or with its
occupants, observations of behaviour, and experiments in the laboratory. For a number of reasons Lough Ine is ideally situated and may
prove unrivalled for this purpose. The lough, together with the Rapids,
the Creek, and the adjacent coast, provides within a limited region environments ranging between calm water and the severest exposure to
Atlantic waves. The Rapids themselves provide a natural experiment
on the effect of current on distribution. The limited tidal range and the
virtual absence of a splash zone within the lough, in contrast to the open
coast, have made possible useful studies in zonation and the role of
exposure to air. The stratification of the waters of the lough in summer,
involving steep gradients of oxygen saturation and pH as well as of
temperature, provides an excellent opportunity for a study of the effects
of these on marine organisms. Finally, the lough, in which many species
of sublittoral animals can be directly observed in accessible, clear,
shallow water, has provided a natural aquarium for many kinds of field
experiment, in particular for the elucidation of relationships between
predator and prey. The narrow tidal range makes it possible to watch
various sublittoral organisms in their natural habitat continuously and
at any stage of the semi-diurnal and lunar cycles of the tide, with the
help of a view box.
Our review starts with a brief description of the topography of Lough
Ine, and with some comments on those geological characteristics which
throw light on the origin of the lough or determine the present features
of the shore. It proceeds to the hydrographical features - the water
currents set up by the tides and the physical and chemical conditions
of the water and the distribution of sediment. It then describes the
distribution of some important and conspicuous inhabitants of the rocky
shores, relating their distribution to current, wave action, exposure to
air, and other inanimate conditions, and to biotic factors such as predation. Systematic problems and problems of natural selection arose
incidentally during the course of our work. They emphasize the severity
of the struggle for existence on the shore, and illustrate the subdivision
of successful animal designs, such as the limpet (Patella) or the dogwhelk (Thais), into models closely adapted to particular and limited
J. A. RITCHING AND F. J. EBLING
I. INTRODUCTION
The object of our work has been to find out how the distribution of
marine organisms in a limited coastal area is determined, how they
react with each other and with their inanimate environment, and how
their numbers are controlled. Our studies involve the assessment of
physical and chemical conditions of the environment, observations of
distribution and abundance of plants and animals, field experiments in
which we interfere either with the inanimate environment or with its
occupants, observations of behaviour, and experiments in the laboratory. For a number of reasons Lough Ine is ideally situated and may
prove unrivalled for this purpose. The lough, together with the Rapids,
the Creek, and the adjacent coast, provides within a limited region environments ranging between calm water and the severest exposure to
Atlantic waves. The Rapids themselves provide a natural experiment
on the effect of current on distribution. The limited tidal range and the
virtual absence of a splash zone within the lough, in contrast to the open
coast, have made possible useful studies in zonation and the role of
exposure to air. The stratification of the waters of the lough in summer,
involving steep gradients of oxygen saturation and pH as well as of
temperature, provides an excellent opportunity for a study of the effects
of these on marine organisms. Finally, the lough, in which many species
of sublittoral animals can be directly observed in accessible, clear,
shallow water, has provided a natural aquarium for many kinds of field
experiment, in particular for the elucidation of relationships between
predator and prey. The narrow tidal range makes it possible to watch
various sublittoral organisms in their natural habitat continuously and
at any stage of the semi-diurnal and lunar cycles of the tide, with the
help of a view box.
Our review starts with a brief description of the topography of Lough
Ine, and with some comments on those geological characteristics which
throw light on the origin of the lough or determine the present features
of the shore. It proceeds to the hydrographical features - the water
currents set up by the tides and the physical and chemical conditions
of the water and the distribution of sediment. It then describes the
distribution of some important and conspicuous inhabitants of the rocky
shores, relating their distribution to current, wave action, exposure to
air, and other inanimate conditions, and to biotic factors such as predation. Systematic problems and problems of natural selection arose
incidentally during the course of our work. They emphasize the severity
of the struggle for existence on the shore, and illustrate the subdivision
of successful animal designs, such as the limpet (Patella) or the dogwhelk (Thais), into models closely adapted to particular and limited