Numerical Analysis of the Aggregation Behavior of Discolaimus major and Laimydorus baldus (Nematoda: Dorylaimida) at Feeding Sites

Discolaimus major與Laimydorus baldus (Nematoda: Dorylaimida )在覓食站聚集行為的數據分析

A.L. Bilgrami and Rashid Pervez

《Acta Zoologica Taiwanica》 11卷2期 (2000/07) Pp. 83-93

https://doi.org/10.6576/AZT.2000.11.(2).2

摘要

本研究針對Discolaimus major與Laimydorus baldus，觀察分析其在捕食過程中，受吸引與聚集而形成的覓食站。分析覓食站時採用下列六種參數；掠食者所形成的覓食站的數目、覓食站持續的時間、掠食者實際的捕食時間、掠食者捕食後聚集持續的時間、掠食者在捕食前、捕食中、捕食後聚集的個體隻數與覓食站的組成比例。這兩種捕食者在這六種參數中的表現均有不同。平均由2到9隻個體形成覓食站，但在進食中與進食後的個體數均會多於進食前。而在進食後，掠食者會持續聚集一段時間。由於掠食者在行體外消化時的食道分泌物與獵物的吸引，造成了掠食者的聚集。覓食站形成所需的花費、覓食站的數目與進食前後的聚集，反映出掠食者其神經感應能力的不同。

關鍵字

吸引 ； 聚集 ； 捕食者 ； 獵物 ； Discolaimus major ； Laimydorus baldus

並列摘要

Pre-feeding and post-feeding attraction and aggregation activities of the dorylaim predators, Discolaimus major and Laimydorus baldus were studied at feeding sites using the following parameters: the number of feeding sites formed by a predator, the duration the feeding site existed, the duration of actual feeding done by the predators, the duration of post- feeding aggregation by predators, the number of predators feeding or showing pre-feeding or post-feeding aggregation, and the rate of site formation. Aggregation behavior of predatory nematodes was analyzed numerically with the help of mathematical equations. D. major and L. baldus showed different values for each of the abovementioned parameters. On an average, 2-9 individual predators were present per feeding site, but the number of feeding individual predators was always more than those showing pre-feeding aggregation at the site. Predators showed prolonged post-feeding aggregation at sites which were formed earlier. Eesophageal secretions of predators released during extra-corporeal digestion, lingering attractants left by the consumed prey individuals, and the concomitant effect of both kinds of secretions in addition to the predator’s own body secretions emanating from at the feeding site were responsible for pre-feeding and post-feeding attraction and aggregation at the feeding site. Different values for the rate of site formation, number of sites formed, and pre-feeding and post-feeding aggregation activities at a feeding site reflected differential predatory and neurosensory abilities of the predators.

並列關鍵字

Attraction ； Aggregation ； Predator ； Prey ； Discolaimus major ； Laimydorus baldus