Impact of Human Disturbance on Fiddler Crab (Uca tangeri) Burrow Morphology, Distribution and Chemistry at Eagle Island, Niger Delta, Nigeria ()
ABSTRACT
Fiddler
crabs are described as ecosystem engineers because of their burrow constructing
ability. It was hypothesized that human activity will impact crab burrows. The
study area was delineated into lowly, medium and highly impacted plots. Crab
holes were randomly counted and their width, length and surface area estimated.
Burrow soils were collected and analyzed for Cadmium (Cd), Lead (Pb) and Zinc
(Zn) using spectrophotometric method (HACH DR 890 colorimeter). The result
indicates that burrow width was significantly different between impacted plots
(P < 0.05). Lowly impacted plot had the largest width while highly impacted
plot had the smallest width. In contrast, there was no significant difference
in burrow length (P > 0.05), but highly impacted plot has the longest length
while lowly impacted plot has the shortest length. Again, the surface area of
crab burrow varies significantly (P < 0.05), and lowly impacted plot had the
largest area (507.95 ± 61.84 cm2) followed by medium (390.30 ± 57.65
cm2) and high (265.16 ± 30.85 cm2) impacted plots.
Similarly, lowly impacted area has more number of burrows (n = 55) followed by medium (n = 30) and highly (n = 23)
impacted plots. Highly impacted plot had the highest Cd and Pb concentration
whereas lowly impacted plot had the highest Zn concentration. This implies that
burrow morphology and chemistry exemplify the level of anthropogenic impact.
Share and Cite:
O. Numbere, A. (2020) Impact of Human Disturbance on Fiddler Crab (
Uca tangeri) Burrow Morphology, Distribution and Chemistry at Eagle Island, Niger Delta, Nigeria.
Open Journal of Marine Science,
10, 191-202. doi:
10.4236/ojms.2020.104015.