BIOL2410 Field trip report
Title: The richness and abundance of Gastropod species vary between two
microhabitats
Acknowledgments: I would like to acknowledge my fellow members in group 3 who
helped to implement the project. I also sincerely appreciate the tutors for their
assistance.
Abstract:
Microhabitat selection for terrestrial and aquatic animals is very important because they
affect the living environment, survival, and reproductive opportunities. The gastropod
species are the most abundant on the rocky shore in New South Wales, Australia. We
conducted a study to compare the difference, measured by the abundance and richness
of gastropod species in two locations which are crevices and the flat surfaces adjacent
to the crevices at Coalcliff Beach. We measured the length and width of the location
samples. We also counted the number of gastropods and identify the species. The
result showed that the abundance and richness of gastropods were significantly higher
in the crevices than on the flat surfaces adjacent to the crevices. The results show that
gastropods tend to live in a location that is structurally more complex, spacious, and
suitable for shelter.
Keywords: Abundance, Crevices, Flat surfaces, Gastropods, Richness
Introduction (338 words):
Microhabitat selection is important for both terrestrial and aquatic animals because it is
a way for them to build a home, avoid extreme climatic conditions, and also avoid
predation. Among marine habitats, rock flats are thermally variable environments and
easily create physical stress for intertidal organisms. However, mobile species can
choose suitable habitats within the allowable range such as flat rocks, pools, and
crevices (Moisez, Seuront & Spilmont 2020). Rock pools and crevices are two habitats
whose depth and variety of obstructions provide better shelter than flat rock.
One of the factors that have a strong influence on the richness and abundance of
gastropod species is the physical structure of the habitat. Often the diversity of
organisms in general increases as the physical structure of the habitat increases in
complexity. A larger habitat structure also means a larger available surface area, thus
attracting more resources (Kovalenko & Pierre 2014). Besides physical factors, the
environment also affects reproduction and other environmental factors. The higher the
habitat structure, the higher the rate of competitive interactions and also the impact on
predation (Kelaher 2003).
, This study focused on the richness and abundance of Gastropod species that varied
between the crevices and flat surfaces adjacent to the crevices. On a flat rock surface,
gastropods are directly exposed to harsh environments. Therefore, they have to
evacuate and find another safer shelter, leading to a change in the diversity of
gastropod species on the rock surface (Colbeck-Tate 2019). Gastropods prefer to live in
crevices where the structure is more complex. It helps them to avoid predation or being
influenced by abiotic or biotic factors.
This study also discussed how the size of the crevices increases or decreases the
number of gastropod species in the crevices. It was hypothesised that the abundance of
gastropod species would be significantly higher in crevice habitats compared to the flat
rocks adjacent to the crevices because the crevices offered refuge shelter and provided
shady conditions. Another hypothesis was that gastropod species were more diverse in
the crevices than on flat surfaces.
Methods (288 words):
A. Study sites
The study was conducted at Coalcliff beach in Sydney, Australia. The latitude of
Coalcliff Beach was -34.2451° S, and the longitude was 150.9770° E. The experiment
started at 9 am and ended at 11 am. There were two sites chosen: one rock platform
located 10 metres away from the Coalcliff SLSC and another rock platform located 30
metres away from Coalcliff SLSC. Each site was limited to 10 x 10 metres to ensure
accuracy.
B. Experimental design and sampling
In the two selected rock platform locations, we found 8 crevices and 8 flat rock surfaces
adjacent to the crevices to identify the gastropods species and count the quantity of
each species. First, we measured the length and width of the chosen spot. After that,
we used the plastic quadrat to focus on measuring the number of gastropods within the
allowable range to ensure each spot is measured equally. We divided the gastropods
found in the spot into groups and used the ID card to identify the name of each species.
Then we counted the number of each species and recorded them. Moved to the next
spots and repeated the above steps.
C. Data analysis
The independent variables were habitat types and the dependent variables were the
number of species and number of individuals per species. Using Minitab, paired T-tests
were used to test if there was a difference in the abundance of Gastropod species in the
two locations. A significance level of 0.05 was used to compare. Mean and standard
Title: The richness and abundance of Gastropod species vary between two
microhabitats
Acknowledgments: I would like to acknowledge my fellow members in group 3 who
helped to implement the project. I also sincerely appreciate the tutors for their
assistance.
Abstract:
Microhabitat selection for terrestrial and aquatic animals is very important because they
affect the living environment, survival, and reproductive opportunities. The gastropod
species are the most abundant on the rocky shore in New South Wales, Australia. We
conducted a study to compare the difference, measured by the abundance and richness
of gastropod species in two locations which are crevices and the flat surfaces adjacent
to the crevices at Coalcliff Beach. We measured the length and width of the location
samples. We also counted the number of gastropods and identify the species. The
result showed that the abundance and richness of gastropods were significantly higher
in the crevices than on the flat surfaces adjacent to the crevices. The results show that
gastropods tend to live in a location that is structurally more complex, spacious, and
suitable for shelter.
Keywords: Abundance, Crevices, Flat surfaces, Gastropods, Richness
Introduction (338 words):
Microhabitat selection is important for both terrestrial and aquatic animals because it is
a way for them to build a home, avoid extreme climatic conditions, and also avoid
predation. Among marine habitats, rock flats are thermally variable environments and
easily create physical stress for intertidal organisms. However, mobile species can
choose suitable habitats within the allowable range such as flat rocks, pools, and
crevices (Moisez, Seuront & Spilmont 2020). Rock pools and crevices are two habitats
whose depth and variety of obstructions provide better shelter than flat rock.
One of the factors that have a strong influence on the richness and abundance of
gastropod species is the physical structure of the habitat. Often the diversity of
organisms in general increases as the physical structure of the habitat increases in
complexity. A larger habitat structure also means a larger available surface area, thus
attracting more resources (Kovalenko & Pierre 2014). Besides physical factors, the
environment also affects reproduction and other environmental factors. The higher the
habitat structure, the higher the rate of competitive interactions and also the impact on
predation (Kelaher 2003).
, This study focused on the richness and abundance of Gastropod species that varied
between the crevices and flat surfaces adjacent to the crevices. On a flat rock surface,
gastropods are directly exposed to harsh environments. Therefore, they have to
evacuate and find another safer shelter, leading to a change in the diversity of
gastropod species on the rock surface (Colbeck-Tate 2019). Gastropods prefer to live in
crevices where the structure is more complex. It helps them to avoid predation or being
influenced by abiotic or biotic factors.
This study also discussed how the size of the crevices increases or decreases the
number of gastropod species in the crevices. It was hypothesised that the abundance of
gastropod species would be significantly higher in crevice habitats compared to the flat
rocks adjacent to the crevices because the crevices offered refuge shelter and provided
shady conditions. Another hypothesis was that gastropod species were more diverse in
the crevices than on flat surfaces.
Methods (288 words):
A. Study sites
The study was conducted at Coalcliff beach in Sydney, Australia. The latitude of
Coalcliff Beach was -34.2451° S, and the longitude was 150.9770° E. The experiment
started at 9 am and ended at 11 am. There were two sites chosen: one rock platform
located 10 metres away from the Coalcliff SLSC and another rock platform located 30
metres away from Coalcliff SLSC. Each site was limited to 10 x 10 metres to ensure
accuracy.
B. Experimental design and sampling
In the two selected rock platform locations, we found 8 crevices and 8 flat rock surfaces
adjacent to the crevices to identify the gastropods species and count the quantity of
each species. First, we measured the length and width of the chosen spot. After that,
we used the plastic quadrat to focus on measuring the number of gastropods within the
allowable range to ensure each spot is measured equally. We divided the gastropods
found in the spot into groups and used the ID card to identify the name of each species.
Then we counted the number of each species and recorded them. Moved to the next
spots and repeated the above steps.
C. Data analysis
The independent variables were habitat types and the dependent variables were the
number of species and number of individuals per species. Using Minitab, paired T-tests
were used to test if there was a difference in the abundance of Gastropod species in the
two locations. A significance level of 0.05 was used to compare. Mean and standard
