How Biodiversity of Fish Population Change Across Depth Habitats in Indian River Lagoon? - Research Essay Sample

5 pages
1333 words
Carnegie Mellon University
Type of paper: 
This essay has been submitted by a student.
This is not an example of the work written by our professional essay writers.


The study seeks to define and describe the biodiversity of the fish population and how it changes with depth in the Indian Lagoon River. Fish were caught measured and released in the knee-deep, waist-deep, and chest-deep waters. The results showed a decrease in the size of fish in mm as we progress to the deep waters. This underlines the conservation efforts that should be put in the shallow waters of the lagoon to sustain biodiversity.

Trust banner

If this sample essay on"How Biodiversity of Fish Population Change Across Depth Habitats in Indian River Lagoon? - Research Essay Sample" doesn’t help,
our writers will!

General Background

Biodiversity is the variety of existing life, and the study can be at different levels. The biodiversity can include all the different species on the earth and on a smaller scale, we can consider a pond or a lagoon ecosystem as we were are doing. The majority of people recognize biodiversity by species, and a species means a group of organisms that can freely interbreed to produce offspring.

The lagoon originates from the ocean serving as abrading ground for the lagoon and pelagic fish species. The lagoon gives revenues of up to $300 million annually from the sale of fish. This figure accounts for 90% of Florida clam landing a 50% of fish landing on the East coast of Florida. Apart from fishing the Lagoon produces $2.1 Billion in citrus revenue and returns $ 300 million annually in marine sales and boat sales.

The Indian River Lagoon is home to about 2100 plant species and 2200 animal species making it the most inhabited ecosystem in North America. The lagoon also sustains 320 species of birds and 300 species of fish. The bird population is a record in North America. Thirty-six unique or endangered species find a home here, and this underlines the importance of its conservation.

Potential species decline in the lagoon was noted as a matter of national concern (Defreese,1991)Understanding the interactions among the species in the Environment is important in ensuring the sustainability of the Indian River Lagoon and therefore preventing cases of extinction(Wilson,1988). The ecological and economic value of the lagoon makes it a crucial area in conservation efforts.

Previous studies diversity in the lagoon is high and this has been attributed to the overlap of the tropical Caribbean and temperate Carolinian fish population. Snelson in his 1993 research counts 337 species in the lagoon associated with freshwater. Gilmore personally notes an increase to 371. Gilmore et al. (1981b) in the 13 habitats lists 682 species from the lagoon including the continental shelf.

Research on distribution shows diversity in the northern portion is half that in the southern part (Snelson 1983).In the south part of the lagoon at the Florida East Coast, most species reach their northern distribution limits. Snelson notes a different case in the north of the lagoon where only one temperate species reaches its southern boundary. He attributes the differences to habitat diversity, latitude and climate, and ocean access. Tropical species and families start disappearing as we move to the north and that is because of killing in the cold spell (Finch, 1917: Miller, 1940, Gunter and Hall, 1963. Gilmore et al.1978 b . Snelson and Bradley, 1978)

Gilmore takes note of the reduction of species within a habitat. Seagrass habitat has the highest diversity and density of fish. Seagrass bed was found to have nine times the population of fish in the sand. Other studies that show that Seagrass cover provides a good indicator of fish density 9 Schooler,1997,1980; Peterson, 1981; Gilmore et al.,1983 b; Kerschner, 1983, Mulligan and Snelson, 1983; Stoner, 1983a; McNeese, 1986).

Rationale, Research Question, and Hypothesis


There is importance in understanding the complexity of depth and how it affects the distribution of species in the lagoon. The study makes it possible to comprehend the relationship between diversity and depth. In indifference, we looked at the density and number of species, but more effort was directed at the population of a particular species as opposed to the variety of species. There is a general assumption that the deepest parts of the waters have the majority of the fish and this study helps demystify this notion. It insists on conservation efforts being concentrated at the shores.

Research question

Due to the constant belief in deep-sea fishing, we set out to find out how true that is to the lagoon. This leads to the research question:

1. How does the biodiversity of the fish population change across depth habitats in the Indian River Lagoon?


1. The population decreases with an increase in depth

2. Near the shallow waters exist Seagrass that affect the population and diversity of fish. As one launches to the deep parts, the Seagrass reduces due to decreased penetration of light, and this results in a decline in fish population and diversity.

Methods and Results

How biodiversity of fish population change across depth habitats in Indian River Lagoon.

In knee-deep waters we had 13 species, in waist-deep, there were 14, and in chest-deep, there were nine species. From this trend, we can conclusively note that the fish species diversity reduces with an increase in depth of the waters.

In knee-deep waters, anchovy, mojarra, and mullet are the leading I terms of numbers at 1420,170 and 129 respectively.

In the waist-deep waters, Mullet becomes less as Croaker replaces it in the prominence list. The number of anchovies reduces to 559, Mojarra reduces to ten, and though Croaker gains the numeric advantage, it reduces from 69 to 28.

In deep chest waters, anchovy, Goby, and mallet become prominent in that order. Anchovy cuts to 38. Mullet gains back to the top three, it increases from 4 to 14 as Goby increase to 22.

Regarding size, knee-deep had the highest numbers being in clusters 4150 and 5160 showing 22 and 25 in anchovy population. Mullet population had groups 2130 and 3140 leading with 27 and 13 respectively. Mojarra had clusters 2130, 3140, and 4150 being the leading with 8, 22, and 8 being their population. Anchovy, Mojarra, and Mullet were the leading species in that order.

Anchovy in the waist-deep waters has 3140, 41509, and 5160 as the modal classes. The classes do not differ greatly from knee-deep water. Mullet in the waist-deep waters have smaller fish with the prominent class being2130. Mojarra maintains their modal class at knee-deep and waist-deep waters. Anchovys modal class changes from 5160 in the knee-deep waters to 4150 in the waist-deep waters and maintain at 4150 in the chest-deep waters.


All the species have a decrease in number as the depth of the water increases. Gilmore, 1978 categorizes this as a reduction of species within a habitat. Gilmore explains this scenario is associated with Seagrass. The diversity is determined by species diversity in the habitat (Gilmore, 1978). Seagrass growth depends on the penetration of light which reduces with an increase in depth. Seagrass habitat has the highest density and diversity something that I agree with Gilmore about.

The increased number of algae specifically macroalgae in and outside Seagrass beds are habitats for small fish. This explains why the fish is abundant in the shallows. Goby and Pipefish are associated with a high number of drift algae (Snelson, 1980; Kulczycki et al., 1981; Mulligan and Snelson, 1983).

Some fish got captured more than once, and that reduces the efficiency of the study. Seasonality might have affected the results gathered regarding size and distribution. Selective gear also needs to be considered for drop nets under capture schooling plankton-eating species, and daytime trawling underrepresents those associated with sediment.

There is a need to consider species-specific research when checking on size. As others may be declining in size, other species can show an increase.

Works Cited

Church, Christopher M. "Indian River Lagoon: An Environmental History by Nathaniel Osborn." Journal of Southern History 83.1 (2017): 192-93. Web.

Durden, Wendy. "Abundance, Distribution, and Group Composition of Indian River Lagoon Bottlenose Dolphins (Tursiops truncatus)." Aquatic Mammals 37.2 (2011): 175-86. Web.

"Population Ecology of Pagurus Maclaughlinae Garcia-Gomez (Decapoda: Anomura: Paguridae) In The Indian River Lagoon, Florida." Journal of Crustacean Biology 14.4 (1994): 686-99. Web

Gilmore, R. Grant. "Notes on the Opossum Pipefish, Oostethus lineatus, from the Indian River Lagoon and Vicinity, Florida." Copeia 1977.4 (1977): 781. Web

Snelson, Franklin F., and Sherry E. Williams. "Notes on the Occurrence, Distribution, and Biology of Elasmobranch Fishes in the Indian River Lagoon System, Florida." Estuaries 4.2 (1981): 110. Web.

Barile, D., and K. Duhring. "The Indian River Lagoon - Impacts from Spanish Conquistadors to Man in Space." Oceans '87 (1987): n. pag. Web.

If you want discreet, top-grade help, order a custom paper from our experts.

If you are the original author of this essay and no longer wish to have it published on the SuperbGrade website, please click below to request its removal: