Seagrass-Watch Magazine Issue 47 - March 2013 | Page 42

Philippines

Davao
threats
gulf
Article by
Della Grace G. Bacaltos
& Helen W. Noel

Photography by
Della Grace G. Bacaltos,
Helen W. Noel
& Len McKenzie

D

AVAO GULF IS LOCATED in the
southeastern part of Mindanao,
the second largest island in the
Philippines. The Gulf if a vast area
covering about 6,550 square kilometres
with a coastline measuring approximately
464 kilometres. A key marine ecosystem
of Davao Gulf is its seagrass meadows,
which cover approximately 305 hectares.
Eleven seagrass species have been
identified in Davao Gulf including:
Cymodocea rotundata, C. serrulata,
Enhalus acoroides, Halodule uninervis, H.
pinifolia, Halophila decipiens, H. minor,
H. ovalis, H. spinulosa, Thalassia
hemprichii, Syringodium isoetifolium,
and an unidentified species of Halophila.
The five most dominant species in terms of
percent frequency and abundance were
Halophila ovalis, Enhalus acoroides,
Thalassia hemprichii, Halodule uninervis,
and Cymodocea rotundata. Among the
dominant seagrass species identified,
Halophila ovalis has the highest percent
frequency of occurrence (64%), which
could be found in all areas in Davao Gulf,
while the least was the Halophila decipiens
with a percent frequency of 1%.
The highest shoot density was for
Halophila ovalis (240 shoots m -2 ).
Relatively high density mean values were
also obtained for Halodule uninervis and
Thalassia hemprichi H