Abstract:
The relative abundance and diversity of a multispecies fishery in Brgy.
Sta. Monica, Infanta, Quezon, were studied using catches from beach
seines and drift longlines from January 2003 to February 2003.
Approximately 9,794 individuals (TW=96,688.5 g) of at least 58 species
belonging to 37 genera and 26 families were caught by these gears during
the study. Encrasicholina punctifer (RA=46.21% and RD=76.67%) and
Nemipterus bathybius (RA=14.82% and RD=22.28%) were the most
abundant and dominant in the beach seine (CPUE=10,468.83 g/hr) and
drift longline (CPUE=955.84 g/hr) catch, respectively. Majority of species
with n>10 that were tallied for their size distribution had mean lengths
significantly less (P<0.05) than the reported mean lengths of the Food and
Agriculture Organization (FAO) in 1999 and Fish Base in 2000. Family
Leiognathidae and Trichiuridae had the shortest and longest sizes with
mean lengths of 6 cm and 49 cm, respectively. Isometric and negative
allometric growth was exhibited by the beach seine and drift longline
catch, respectively. Isometric growth was exhibited by the fish assemblage
of Brgy. Sta. Monica whose length-weight relationship (LWR) had a mean
exponent (b=2.77), which was not significantly less than 3 (t=1.105,
df=15, P>0.05). Diversity indices for the drift longline (H’=4.06; D=6.08;
and J=1.16) were higher than those computed for the beach seine
(H’=1.08; D=2.84; and J= 0.33). Mean diversity index for Brgy. Sta.
Monica is as follows: H’=1.28; D=6.20; and J=0.32.
