Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Related Publications
• Parameters
• Instruments
• Deployments
• Project Information
• Funding

This dataset is part 2 of a 2 part manipulative experiment to investigate the existence of cooperative synergy in defensive behaviors of ‘guard’ crustaceans. Please reference the Related Datasets for additional datasets.

Related Datasets:

• McKeon_et_al_2012 Multiple Defender Effects: https://www.bco-dmo.org/dataset/727093
• McKeon_et_al_2012 Multiple Defender Effects Symbiont Behavior: https://www.bco-dmo.org/dataset/727125 (current page)

We used behavioral observation methods based on those of Glynn (1980) to measure the reaction of Pocillopora exosymbionts to Culcita presence at different vertical locations on the colony. A coral colony with both Alpheus and Trapezia exosymbionts was placed on an elevated pedestal within a large seawater aquarium. Culcita was presented to the coral sequentially in two different experimental positions, where Culcita was held against the side or the top of the coral colony, respectively. Each trial alternated starting position and lasted 3 min with a 5-min rest period between treatments. Defensive behaviors were scored within 3 min with actions recorded on a per minute basis for proximity and degree of contact of the exosymbionts with the Culcita. If the Trapezia were viewed by the observer to show any response to the presence of the Culcita (usually adjusting its position to directly below the Culcita while remaining deep within the branches of the coral), it was given a score of 0.25. If the Trapezia advanced further, to within 2 cm of the Culcita, then it was given a score of 0.5 points. One point was added each time the Trapezia attacked by snapping at the body or tube feet of the Culcita, and an additional two points were given if the Trapezia attack resulted in a cut to the Culcita or removal of tube feet. If the Trapezia retreated and then re-engaged, the scoring system was restarted and all bouts were summed. The defensive snap of Alpheus involves a distinctive snapping sound (Glynn 1980), each of which was given a score of 1 point.

BCO-DMO Processing:

• added conventional header with dataset name, PI name, version date
• modified parameter names to conform with BCO-DMO naming conventions

Description from NSF award abstract:
Ecologists have long been interested in the factors that drive spatial and temporal variability in population density and structure. In marine reef systems, attention has focused on the role of settlement-the transition of pelagic larvae to a benthic stage-and on density-dependent processes affecting recently settled juveniles. Recent data suggest that co-variance in settlement and subsequent density-dependent survival can obscure the patterns of density dependence at larger scales, a phenomenon called cryptic density dependence. This research will explore the mechanisms that underlie the spatial covariance of settlement and site quality - a process that has received little attention in the standard paradigm. These mechanistic studies of cryptic density dependence will facilitate the development of new frameworks for fish population dynamics that incorporate larval ecology, habitat quality, density dependence, life history, and the patterns and implications of spatial covariance among these factors. More generally, the work provides a specific empirical context, and a general theoretical treatment, of cryptic heterogeneity (hidden individual variation in demographic rates).

Note: Drs. Craig W. Osenberg and Ben Bolker were at the University of Florida at the time the NSF award was granted. Dr. Osenberg moved to the University of Georgia during the summer of 2014 (current contact information). Dr. Bolker moved to McMaster University in 2010 (current contact information).