This book provides a glimpse into the recent researches on animal ecology, their reproductive strategies and the ecological problems of various environments in India and abroad. The book also reviews the progress made in the field in past few decades. The present volume of the book series Perspectives in Animal Ecology and Reproduction is the compilation of the twenty seven quality research and review articles contributed by leading experts and comprises the topics like- Occurrence of amphizoic amoebae in domestic water supply; Study of Vibrio parahaemoliticus through ERIC- PCR and REP- PCR for development of fish and human health management; Seasonal fluctuation of nutrients and phytoplankton in Igoumenitsa Bay; Phagocytosis of charcoal particulate as immunological marker of azadirachtin exposure; Estimation of activity of some metabolic enzymes in the serum of fish Cyprinus carpio as a function of their growth in juveniles; Amelioration of anti-oxidant vitamins on ciprofloxacin induced toxic changes in blood; Impact of chromium on haematological parameters in fresh water fish Channa punctatus; Behavioural alterations in fresh water stinging catfish, Heteropneustes fossilis (Bloch) after fluoride toxicity; Traits related to social hierarchy in ruminant ungulates; Feeding and reproduction of Artemia franciscana from Basrah; Ultrastructural studies of vitellogenesis in Asellus aquaticus; Photoperiod and biological rhythms in regulation of avian reproduction; Environmental modulations and reproduction: the favourable and unfavourable paradigms; Active immunization against riboflavin carrier protein prevents from pregnancy establishment in sub-human primate. The book, with its balanced approach will be a valuable, and an important research manual, that will stimulate interest and satisfy the need of the ecologists, toxicologists, physiologists, reproductive biologists, environmentalists and post graduate students of ecology and environmental sciences in various aspects.