192
WILLIAM MACNAE
Once the burrow has been made the male sets about attracting a
female by means of a very characteristic sexual display. On the
approach of a female the male will raise himself slightly on his pectoral
fins. The first dorsal fin, with its prolonged flexible orange rays, and
the second dorsal fin will be erected. Then, prefaced by vigorous and
repeated sinuous movements of the tail, and a concave arching of the
body with both head and tail raised off the surface of the mud, the male
will jump some three times. The first of these is the highest leap and
the last is a movement in which he scarcely pushes himself up on his
pectoral fins. These actions will be repeated as often as is necessary to
attract the female. As soon as the female begins to approach, the male
will raise himself 011 his pectorals and inflate his throat which has
become orange coloured during the breeding season. Finally he will
turn towards the burrow with the female following close behind. The
male will enter, the female will hesitate at the entrance. After a short
time the male will reappear and start blowing bubbles. The female
may then enter the burrow and pairing seems to become established.
When pairing is successful a region of around 25 ern (1 ft) from the
burrow becomes, according to Khoo, the scene of a very vigorous
display in defence of the area. The male jumps around in an abandoned
fashion and chases away any other males while the female sits in the
mouth of the burrow. Usually such a defence and display is successful
in driving off rivals and retaining possession of the female, but occasionally the active display of a male just beyond the edge of a territory
would induce a female to leave her first choice (Khoo saw this happen
once only).
Fighting and confrontation is common between individual males
while they are feeding, and also any crab coming within the area of
influence of a specimen of P. chrysospilos is attacked and driven off.
The description given by Khoo was based on observations made
from a boat stranded on the mud, or some similar perch. These leave
certain questions unanswered. My own observations at times of rising
tides and of falling tides suggest that breeding individuals both of
P. chrysospilos and of P. schlosseri remain a t their burrows when these
are submerged. On two occasions the flood tide was seen to overflow
a pair of P. chryospilos at the entrance to their burrow. These fish did
not swim away as did unmated individuals nearby. On three occasions
on a falling tide a pair of P. schlosseri were seen reclining on the inside
slope of the wall of a nest burrow. They had not been disturbed and
had not just arrived there from elsewhere.
What, then, does happen to paired individuals when the tide flows
over them:!
WILLIAM MACNAE
Once the burrow has been made the male sets about attracting a
female by means of a very characteristic sexual display. On the
approach of a female the male will raise himself slightly on his pectoral
fins. The first dorsal fin, with its prolonged flexible orange rays, and
the second dorsal fin will be erected. Then, prefaced by vigorous and
repeated sinuous movements of the tail, and a concave arching of the
body with both head and tail raised off the surface of the mud, the male
will jump some three times. The first of these is the highest leap and
the last is a movement in which he scarcely pushes himself up on his
pectoral fins. These actions will be repeated as often as is necessary to
attract the female. As soon as the female begins to approach, the male
will raise himself 011 his pectorals and inflate his throat which has
become orange coloured during the breeding season. Finally he will
turn towards the burrow with the female following close behind. The
male will enter, the female will hesitate at the entrance. After a short
time the male will reappear and start blowing bubbles. The female
may then enter the burrow and pairing seems to become established.
When pairing is successful a region of around 25 ern (1 ft) from the
burrow becomes, according to Khoo, the scene of a very vigorous
display in defence of the area. The male jumps around in an abandoned
fashion and chases away any other males while the female sits in the
mouth of the burrow. Usually such a defence and display is successful
in driving off rivals and retaining possession of the female, but occasionally the active display of a male just beyond the edge of a territory
would induce a female to leave her first choice (Khoo saw this happen
once only).
Fighting and confrontation is common between individual males
while they are feeding, and also any crab coming within the area of
influence of a specimen of P. chrysospilos is attacked and driven off.
The description given by Khoo was based on observations made
from a boat stranded on the mud, or some similar perch. These leave
certain questions unanswered. My own observations at times of rising
tides and of falling tides suggest that breeding individuals both of
P. chrysospilos and of P. schlosseri remain a t their burrows when these
are submerged. On two occasions the flood tide was seen to overflow
a pair of P. chryospilos at the entrance to their burrow. These fish did
not swim away as did unmated individuals nearby. On three occasions
on a falling tide a pair of P. schlosseri were seen reclining on the inside
slope of the wall of a nest burrow. They had not been disturbed and
had not just arrived there from elsewhere.
What, then, does happen to paired individuals when the tide flows
over them:!