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  • A case study of sequential colonization: intra- and interspecific patterns of recovery in a hydrologically pulsed ecosystem
Title: A case study of sequential colonization: intra- and interspecific patterns of recovery in a hydrologically pulsed ecosystem
Community assembly is influenced by disturbance intensity, sequential colonization (arrival order) of species, and interactions between species arriving early and species arriving later. We documented both intra- and interspecific patterns of colonization following hydrological disturbance using a 20-year time series of marsh-fish density at 21 study sites located in the Everglades, Florida, USA, as a case study of sequential colonization. The critical swimming speed (UCRIT) of 20 juveniles and 20 adults for six species was estimated using UCRIT tests to evaluate if UCRIT predicted timing of re-colonization. We observed a consistent pattern of species colonization over 500 disturbance events. On average, juveniles of early arriving species were collected prior to adults, while adults consistently appeared prior to juveniles for late-arriving species. Density at first collection was inversely correlated with arrival order; early arriving species tended to have higher density when first collected following marsh re-flooding than later arriving ones. Females consistently arrived before males for all species where sex could be identified. Neither absolute nor size-adjusted UCRIT was correlated with arrival order. Although interspecific colonization was highly repeatable, intraspecific differences among demographic groups were species-specific and possibly tied to reproductive biology and juvenile life history. Juvenile early arrival may indicate rapid colonization of pregnant females (Poeciliidae), diapausing eggs laid before marsh drying, or early development of robust swimming capacity (Cyprinodontidae and Fundulidae); in the Everglades, water currents are absent or too weak to support larval drift as an important mechanism. Stage- and sex-specific UCRIT and reproductive traits such as embryo diapause in oviparous species need more attention to understand successional dynamics following disturbance in aquatic communities.  more » « less
Award ID(s):
2025954
PAR ID:
10510068
Author(s) / Creator(s):
; ;
Publisher / Repository:
Springer Nature
Date Published:
Journal Name:
Environmental Biology of Fishes
Volume:
107
Issue:
3
ISSN:
0378-1909
Page Range / eLocation ID:
347-367
Subject(s) / Keyword(s):
Stage-specific UCRIT Disturbance Everglades Sex-specific colonization Sequential colonization
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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