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P.L. Colin
The larger greenthroat parrotfi sh ( Scarus prasignathos ), tan-faced parrotfi sh
( Chlorurus frontalis ) and ringtail surgeonfi sh ( Acanthurus blochii ) migrate along
pathways through the aggregation areas of the smaller species (and while the smaller
fi shes are spawning) to an area near the edge of a deep tidal channel at least 1.5 km
distant (Fig. 5.14b ) where they spawn. An hour later they return along the same
lines, moving along the depth contours (3–6 m deep) of the reef front to their home
ranges. The humphead wrasse, Cheilinus undulatus , is the largest known RA
species and its maximal daily migrations, in Palau on the order of 5–10 km (Colin
2010 ) and about 10 km at Layang Layang atoll, South China Sea; that distance limited
by the atoll size (Nicholas Pilcher 2005) may represent near an upper limit to RA
species daily migration distances.
TA species migrate to and from sites usually for a specifi c lunar or seasonal
period and tend to be predatory species able to forego feeding for prolonged periods
(Chap. 2 ). Nassau grouper have documented migration distances to spawning aggregations of 150–250 km along unbroken reef tracts (Bahamas – Colin 1992 ; Bolden
2000 ; Belize-Yucatan - Carter et al. 1994 ) and lesser distances among islands and
reefs isolated by deep waters (Belize, Glover’s Reef 35 km – Starr et al. 2007 ; US
Virgin Islands, St. Thomas, 6–33 km, St. Croix, 5–18 km – Nemeth et al. 2007 ) .
Fig. 5.14 Daily migration patterns of fi shes which form resident aggregations ( RA ) on shallow
reefs can differ among fi shes. For Lighthouse Reef, Koror, Palau, ( a ) small parrotfi shes and surgeonfi shes migrate only short distances to form a band of spawning fi shes on the seaward margin
of the reef, while ( b ) somewhat larger species migrate at least a few km along the shallow reef to
spawn on the margin of the deep tidal channel (Photo and unpublished data: Patrick L. Colin)
P.L. Colin
The larger greenthroat parrotfi sh ( Scarus prasignathos ), tan-faced parrotfi sh
( Chlorurus frontalis ) and ringtail surgeonfi sh ( Acanthurus blochii ) migrate along
pathways through the aggregation areas of the smaller species (and while the smaller
fi shes are spawning) to an area near the edge of a deep tidal channel at least 1.5 km
distant (Fig. 5.14b ) where they spawn. An hour later they return along the same
lines, moving along the depth contours (3–6 m deep) of the reef front to their home
ranges. The humphead wrasse, Cheilinus undulatus , is the largest known RA
species and its maximal daily migrations, in Palau on the order of 5–10 km (Colin
2010 ) and about 10 km at Layang Layang atoll, South China Sea; that distance limited
by the atoll size (Nicholas Pilcher 2005) may represent near an upper limit to RA
species daily migration distances.
TA species migrate to and from sites usually for a specifi c lunar or seasonal
period and tend to be predatory species able to forego feeding for prolonged periods
(Chap. 2 ). Nassau grouper have documented migration distances to spawning aggregations of 150–250 km along unbroken reef tracts (Bahamas – Colin 1992 ; Bolden
2000 ; Belize-Yucatan - Carter et al. 1994 ) and lesser distances among islands and
reefs isolated by deep waters (Belize, Glover’s Reef 35 km – Starr et al. 2007 ; US
Virgin Islands, St. Thomas, 6–33 km, St. Croix, 5–18 km – Nemeth et al. 2007 ) .
Fig. 5.14 Daily migration patterns of fi shes which form resident aggregations ( RA ) on shallow
reefs can differ among fi shes. For Lighthouse Reef, Koror, Palau, ( a ) small parrotfi shes and surgeonfi shes migrate only short distances to form a band of spawning fi shes on the seaward margin
of the reef, while ( b ) somewhat larger species migrate at least a few km along the shallow reef to
spawn on the margin of the deep tidal channel (Photo and unpublished data: Patrick L. Colin)