Sympatric Spawning of the Damselfishes Chromis Fumea and Pomacentrus Coelestis on the Northern Coast of Taiwan

臺灣北部海岸燕尾光鰓雀鯛與變色雀鯛間同域生殖現象及交互作用

詹榮桂(Rong-Quen Jan)

《Zoological Studies》 36卷1期 (1997/01) Pp. 26-32

摘要

燕尾光鰓雀鯛（Chromis fumea）和變色雀鯛（Pomacentrus coelestis）兩種魚類都是底棲性產卵者，不過牠們平時並未在海域中佔據領域。在1986年的生殖季節裡，於臺灣北部海岸附近海域內的一個研究區域，共觀察到2149個燕尾光鰓雀鯛的以及890個變色雀鯛的生殖巢。兩種雀鯛都是產卵時聚集成群的群性產卵者。在調查區內，燕尾光鯉、雀鯛的巢分布在四個產卵區，而變色雀鯛則在五個區。其中有兩個產卵區是兩者都利用到的，亦即牠們的產卵區有相重疊的現象。其中1/3的燕尾光鰓雀鯛以及12.1%的變色雀鯛的巢出現在重疊區域內。這兩種雀鯛的巢分別築在不同的基質上：燕尾光鰓雀鯛築在平坦空曠的海底基質（礁石）的上表面，而變色雀鯛則在礁石下挖掘出洞穴並在裡面產卵。當此二種雀鯛同時在同一區域產卵時，之間會發生一些互相干擾的現象：在單純的個體與個體之間的相遭遇間，燕尾光鰓雀鯛（較早築巢產卵）能夠防止競爭者在附近築巢，而在另外一方面，當變色雀鯛成群出現時，燕尾光鰓雀鯛會被迫放棄牠們已建的巢，而變色雀鯛則會從原來燕尾光鰓雀鯛築巢的地點築起巢來。

關鍵字

築巢基質 ； 雀鯛科 ； 資源分配 ； 生殖季節

並列摘要

The damselfishes Chromis fumea and Pomacentrus coelestis are both free-ranging demersal spawners; they generally do not occupy a permanent substrate. A total of 2149 nests of C. fumea and 890 nests of P. coelestis were found in the study area on the northern coast of Taiwan in the spawning season of 1986. Both species spawned in groups. Sympatrie spawnings, which involved about 1/3 of C. fumea nests and 12.1% of P. coelestis nests, occurred at some of the spawning sites. The 2 damselfish species nested mainly on different substrates: C. fumea on open substrate, with P. coelestis in small burrows or depressions excavated beneath boulders. However, interference occurred whenever they spawned sympatrically. When the interactions involved only 1 individual of each species, C. fumea (which is larger in size and built nests first) was able to prevent the competitor from building a nest in the neighboring area by active aggression. In comparison, when the 2 species encountered each other in groups, harassment from P. coetestis was observed to force C. fumea to abandon their nests. P. coelestis SUbsequently built nests at the site taken over from the latter fish.

並列關鍵字

Nesting substrate ； Pomacentridae ； Resource partitioning ； Spawning season