THE ASPECT OF THE BIOLOGY OF Periophthalmus barbarus mudskipper, FROM UTA-EWA ESTUARIES IN IKOT ABASI L.G.A., AKWA IBOM STATE, NIGERIA

0
19

TABLE OF CONTENTS

Contents Pages
Cover page
Title pages…………………………………………………………….i
Abstract………………………………………………………………ii
Declaration…………………………………………………………..iii
Certification………………………………………………………… iv
Dedication …………………………………………………………… v
Acknowledgment …………………………………………………… vi
List of table…….…………………………………………………… vii
List of figures…………………………………………………………viii
Table of contents …….………………………………………………ix
CHAPTER ONE: INTRODUCTION……………………………… 1
Background of study 1
Statement of problems
Justification
Significance of the study
Aims and objective of study
CHAPTER TWO
Literature review

CHAPTER THREE: MATERIAL AND METHOD
Describe of the Study Area
Collection of samples
Sample preparations
Sexual dimorphism
Sex ratio
Gonadosomatic Index
Hepatosomatic index
Condition Index
Length and weight measurements

CHAPTER FOUR:
Results

CHAPTER FIVE
Discussion
Recommendation
Conclusion
References
Appendix

CHAPTER ONE
1.0 INTRODUCTION
1.1 Background of study
Fresh water fish constitute 41% of known species of fish. They dwell in fresh waters like lakes and rivers where salinity is as less as 0.05% (Karthik, 2010). Fish is one of our most valuable sources of protein food worldwide; people obtain about 25% of their animal protein from fish. It is the most easily affordable source of animal protein to the average Nigerian.
Periopthalmus barbarus is an amphibious fish and is commonly known as mudskipper. This is a type of fish species that lives in burrows in the intertidal saline swamps in estuaries, creeks and lagoons. Together with the other members of the subfamily Oxudercinae, they form a diverse group of species which colonised semi-terrestrial habitats in intertidal and supra-tidal coastal swamps (Takita et al. 1999; Polgar&Crosa 2009). It occupies a salient ecological niche and is a valued component of some artisanal catches being exploited either for use as baits in hook and line fisheries, for human consumption or for use in traditional medicinal preparations where aphrodisiac properties are attributed to its flesh (Clayton 1993, Etim 2002).
They are investigated for their biological and eco-toxicological studies, to determine its potential use as a bio-indicator in environmental assessments of coastal waters, tropical or subtropical soft bottom intertidal systems. Mudskippers have been utilized as model species in several ecotoxicological studies (Polgar& Lim 2011) to assess the presence of toxicants in coastal areas and study their effects on intertidal residents. Several contaminants have been investigated, from heavy metals (e.g. Ni et al. 2000) to organochlorine contaminants (e.g. Wong et al. 2006), aromatic hydrocarbons (e.g. Nakata et al. 2009), perfluorinated contaminants (e.g. Nakata et al. 2006), and radionuclide (e.g. Bangera& Patel 1984). Malformations occurring in mudskippers living in polluted areas were recorded by Kruitwagen et al. (2006). This potential would be beneficial for new researches on this species especially for its ecological importance in detecting pollution levels in coastal water ecosystems. Bio-ecological knowledge of this group is essentially required to evaluate its possible use as an ecological indicator for coastal pollution. Mudskippers are entirely different from many other fishes as they can breathe comfortably, in water as well as in land (Journal of entomology and zoology studies 2014). The species is usually cultured and studied ecologically because of their considerable tolerance to environmental stressors, organic and inorganic contaminants. If they are used as food source, it is highly recommended that they should be carefully and periodically monitored for contaminants to assess the health risk to consumers of this species (Journal of entomology and zoology studies 2014). An urgent implementation to maintain the sustainability of natural resource is necessary and prompt environmental remediation measure and ecosystem rehabilitation is also urgently required. A possible elucidation could be related to the mudskippers’ amphibious lifestyle, which may expose them more directly to various contaminants in coastal waters(King 2004). Population dynamics of mudskippers, their easy and cost effective maintenance, and considerable tolerance to changes in water quality parameters have been frequently used, both in aquaculture and in eco-toxicological studies.In polluted coastal areas, mudskippers are the potential bio-indicators and bio-accumulators of pollutants and directly or indirectly related with human health issues, as they are consumed in different regions. Mudskippers absorb and accumulate many different pollutants released into the coastal environment by industrial, agricultural, domestic and transportation activities. The physiological, histological, and embryological changes in mudskippers are considered as strong indicators of water quality parameters. Mudskippers can accumulate very high concentrations of toxic compounds in their tissues(Journal of entomology and zoology studies 2014). Their robustness to environmental stressors and tolerance against many contaminants give them the capacity to be exposed to toxicants without significant effects, and to biomagnifying toxicants in their body tissues. Air breathing fishes like mudskipperscould be considered as a keystone species in tropical mangrove habitats (Journal of entomology and zoology studies 2014). They play an important role in benthic ecology as they prey small crustaceans and graze diatoms and algae from mudflats.

1.2 Statement of Problem
Periophthalmus barbarus apart from being a source of food to obtain protein it can also be use in traditional medicinal preparations where aphrodisiac properties are attributed to its flesh (Clayton 1993, Etim 2002).
P. barbarus can act as model species in several eco-toxicological studies (Polgar& Lim 2011) to assess the presence of toxicants in coastal areas and study their effects on intertidal residents.
Air breathing fishes like mudskippers could be considered as a keystone species in tropical mangrove habitats (Journal of entomology and zoology studies 2014). They play an important role in benthic ecology as they prey small crustaceans and graze diatoms and algae from mudflats.

1.3 Aims and Objectives of Study
This aim of this research work is to know, compare and contrast the aspect of the biology of Periopthalmus barbarus and thereby knowing the importance of the specie.
Studying the fish species can unveil the rate in which the costal water is being polluted because the species acts as a bio-indicator in the aquatic environment.
They are investigated for their biological and eco-toxicological studies, to determine its potential use as a bio-indicator in environmental assessments of coastal waters, tropical or subtropical soft bottom intertidal systems.
Bio-ecological knowledge of this group is essentially required to evaluate its possible use as an ecological indicator for coastal pollution.
This research can also check whether the specie is going extinct or extant.
Protecting and improving the state of coastal waters and mangrove forests ecosystems which are the natural habitat for mudskippers.

1.4 Significance of study
This study focuses on biology of the specie, the influence of the environment on it and how the specie influences the environment and community at large.
Periophthalmus barbarus is sensitive to ambient environment and this potential would be beneficial for new researchers or even the Government on this species especially its ecological importance in detecting pollution levels in coastal water ecosystems and environmental quality program could be established.

1.5 Justification
Many fish dwells in Uta-Ewa creek but their rate of survival in the aquatic environment is low due to some due to the water being polluted by industrial waste and oil spillage.
Periophthalmus barbarus (mudskipper) are abundant in the Uta-Ewa estuary due to their amphibious potentials and their sensitive to ambient environment.
This research work is to ascertain the potential effect of mudskipper to the aquatic environment hence the biology of the fish is being investigated to check the distribution, reproductive index, growth pattern, sex ratio etc.
These components shall be justified during the course the research work.

THE ASPECT OF THE BIOLOGY OF Periophthalmus barbarus mudskipper, FROM UTA-EWA ESTUARIES IN IKOT ABASI L.G.A., AKWA IBOM STATE, NIGERIA