Biomaterial Database

Depth distribution and biological characteristics of the European eel Anguilla anguilla in Lough Ennell, Ireland. 2009

K Yokouchi, and J Aoyama, and M J Miller, and T K McCarthy, and K Tsukamoto

Ocean Research Institute, The University of Tokyo, Tokyo, Japan. kazukiy@ori.u-tokyo.ac.jp

Using a longline survey, a total of 196 European eels Anguilla anguilla were collected at different depths in Lough Ennell (maximum depth 30 m), central Ireland. The catch per unit of effort of A. anguilla that were caught from 1 to 25 m depths was lowest at 0.5-5.0 m and greatest at the deepest depth range (22.5-25.0 m). Sub-samples of A. anguilla from depths of <15 m showed little or no difference in size, sex ratio, age, growth rate, condition factor, length-mass relationship, gonado-somatic index, fin index or eye index with fish from depths of >15 m. All fish examined were female yellow-phase A. anguilla that had ages from 7 to 20 years (mean +/-s.d. = 10.3 +/- 2.9 years), with growth rates from 24.0-60.8 mm year(-1) (mean +/-s.d. = 40.7 +/- 8.5 mm year(-1)). Variations in the growth rates were greater in the shallow group than that of the deep group. This study suggested that deeper regions are important feeding habitats for A. anguilla and that fish in this lake were growing moderately fast compared to similar habitats and areas in the species' range.

UI	MeSH Term	Description	Entries
D007494	Ireland	A country in western Europe, occupying five-sixths of the island of Ireland in the North Atlantic Ocean, west of Great Britain. The capital is Dublin.	Eire,Ireland, Republic of,Irish Free State
D011156	Population Density	Number of individuals in a population relative to space.	Overpopulation,Population Size,Underpopulation,Densities, Population,Density, Population,Population Densities,Population Sizes
D012044	Regression Analysis	Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable.	Regression Diagnostics,Statistical Regression,Analysis, Regression,Analyses, Regression,Diagnostics, Regression,Regression Analyses,Regression, Statistical,Regressions, Statistical,Statistical Regressions
D001824	Body Constitution	The physical characteristics of the body, including the mode of performance of functions, the activity of metabolic processes, the manner and degree of reactions to stimuli, and power of resistance to the attack of pathogenic organisms.	Body Constitutions,Constitution, Body,Constitutions, Body
D005260	Female		Females
D006066	Gonads	The gamete-producing glands, OVARY or TESTIS.	Gonad
D000811	Anguilla	A genus in the Family Anguillidae, Order Anguilliformes, that includes fresh water eels.	Anguillas
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012744	Sex Ratio	The number of males per 100 females.	Ratio, Sex,Ratios, Sex,Sex Ratios
D017753	Ecosystem	A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)	Ecosystems,Biome,Ecologic System,Ecologic Systems,Ecological System,Habitat,Niche, Ecological,System, Ecological,Systems, Ecological,Biomes,Ecological Niche,Ecological Systems,Habitats,System, Ecologic,Systems, Ecologic