FAUNA AND FLORA OF MANGROVE SWAMPS
153
Of the land animals that invade the mangal many remain, in fact,
terrestrial. Birds characteristic of fresh waters are attracted to mangals,
seeking their food in the creeks and channels and nesting in the trees.
Only a few such as the " mangrove kingfishers " are restricted to
mangals. This is even more true of the mammals, amphibians and
reptiles. Insects fall into two groups, some are visitors, bees drawn t o
seek honey from Aegiceras and the rhizophoras ; some are parasites, the
beetles which bore into the living trees, and the coccids which often
cover the leaves and young twigs of members of the Rhizophoraceae ;
some, such as the " tailor ants ", come after the coccids ; some beetles
come to bore into dead branches and trunks. All these are still
terrestrial. Other insects have larvae which live in the uppermost
layers of the soil and only here ; these are dependent on the soils at this
level for their existence but not on the mangal, for they persist even
when the mangal has been cleared. This is true of ceratopogonid larva.,e
in northern and eastern Australia, where clearing of mangroves has not
reduced the nuisance created by adult forms of these midges, so often
miscalled sandflies.
A. Birds associated with mangals
One or other of several cormorants may be seen: Phalacrocorax
carbo (L.) occurs all round the Indian Ocean ; of the smaller long-tailed
species, P . africanus (Gm.) is found in Africa, P. melanogaster Vieillot
in New Guinea and Australia, and P. niger King from India to Borneo.
These last three are similar in size and appearance and are characteristic
of rivers and estuaries. Along African and Australian mangrove
channels cormorants may be frequently seen, yet it is surprising that
they seem to be most uncommon on the coasts of western Malaya and
peninsular Thailand.
Darters Anhinga anhinga (L.) are common ; they are often abundant
in the larger rivers and delta distributaries, but rarely enter the more
purely marine channels of the mangal.
Herons use the channel banks as fishing grounds and often nest
communally with cormorants and darters in the taller trees in the
more isolated parts of the mangal. Egretta alba (L.), the white egret
or white heron, and E . garzetta (L.), the little egret, extend from Africa
to Australia. E . gularis (Bosc.) is said to pick up mud-skipping fish on
the seaward fringes in India, and E . eulophotes (Swinh.) is also found
along the creeks and channels in South East Asia. Nycticorax nycticorax
(L.), the night heron, extends from South Africa to South East Asia
and Hawaii; N . caledonicus (Gm.) replaces it from the Philippines
through Indonesia to Australia. Ardeola grayii (Sykes), the paddy
153
Of the land animals that invade the mangal many remain, in fact,
terrestrial. Birds characteristic of fresh waters are attracted to mangals,
seeking their food in the creeks and channels and nesting in the trees.
Only a few such as the " mangrove kingfishers " are restricted to
mangals. This is even more true of the mammals, amphibians and
reptiles. Insects fall into two groups, some are visitors, bees drawn t o
seek honey from Aegiceras and the rhizophoras ; some are parasites, the
beetles which bore into the living trees, and the coccids which often
cover the leaves and young twigs of members of the Rhizophoraceae ;
some, such as the " tailor ants ", come after the coccids ; some beetles
come to bore into dead branches and trunks. All these are still
terrestrial. Other insects have larvae which live in the uppermost
layers of the soil and only here ; these are dependent on the soils at this
level for their existence but not on the mangal, for they persist even
when the mangal has been cleared. This is true of ceratopogonid larva.,e
in northern and eastern Australia, where clearing of mangroves has not
reduced the nuisance created by adult forms of these midges, so often
miscalled sandflies.
A. Birds associated with mangals
One or other of several cormorants may be seen: Phalacrocorax
carbo (L.) occurs all round the Indian Ocean ; of the smaller long-tailed
species, P . africanus (Gm.) is found in Africa, P. melanogaster Vieillot
in New Guinea and Australia, and P. niger King from India to Borneo.
These last three are similar in size and appearance and are characteristic
of rivers and estuaries. Along African and Australian mangrove
channels cormorants may be frequently seen, yet it is surprising that
they seem to be most uncommon on the coasts of western Malaya and
peninsular Thailand.
Darters Anhinga anhinga (L.) are common ; they are often abundant
in the larger rivers and delta distributaries, but rarely enter the more
purely marine channels of the mangal.
Herons use the channel banks as fishing grounds and often nest
communally with cormorants and darters in the taller trees in the
more isolated parts of the mangal. Egretta alba (L.), the white egret
or white heron, and E . garzetta (L.), the little egret, extend from Africa
to Australia. E . gularis (Bosc.) is said to pick up mud-skipping fish on
the seaward fringes in India, and E . eulophotes (Swinh.) is also found
along the creeks and channels in South East Asia. Nycticorax nycticorax
(L.), the night heron, extends from South Africa to South East Asia
and Hawaii; N . caledonicus (Gm.) replaces it from the Philippines
through Indonesia to Australia. Ardeola grayii (Sykes), the paddy