This dataset is part of an integrated series of experiments to study how dispersal affects the density and relatedness of neighbors, and how the density and relatedness of neighbors in turn affect fitness. Dispersal kernels in a marine bryozoan were empirically estimated in shallow (less than 2 meters) seagrass habitats near the Florida State University Coastal and Marine Laboratory (FSUCML) in St. Teresa, Florida, USA (29° 54' N, 84° 30' W). Most larvae settled within approximately 1 meter of the maternal colony, although some could travel at least 10s of meters.

Table of Contents

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

To estimate dispersal kernels, we quantified the number of settlers at a range of distances from a known source of reproductive colonies. We deployed 172 poles in seven concentric rings in a shallow area (more than 1 meter maximum depth, consistent across the study area) immediately east of the Florida State University Coastal and Marine Laboratory (FSUCML). Each pole was 1.9 centimeter diameter plastic pipe, extending 40 centimeters vertically from the ground, onto which settlement plates were attached. The seven rings had radiuses of 0.25, 0.5, 1, 2, 4, 8, and 12 meters. To ensure a relatively similar sampling effort at each dispersal distance, poles within each radius were placed approximately 1 meter apart (except for the 0.25 meter distance where poles were approximately 40 centimeters apart), resulting in 2, 4, 4, 8, 12, 23, 46, and 73 poles at radiuses of 0, 0.25, 0.5, 1, 2, 4, 8, and 12 meters, respectively. The area consisted mostly of sand, with small patches of short seagrass (mostly Halodule wrightii and Thalassia testudinum). Prior to deploying the poles, the area was thoroughly checked to ensure the absence of B. neritina colonies within a roughly 30 x 30 meter area.

Over a period of two months (between 17^th October and 14^th December 2017), we deployed settlement plates (roughened acetate sheets wrapped around the pole) on five occasions. On two ‘trial’ occasions, we placed seven adult reproductive colonies of B. nertina in the center of the array. Seven colonies, rather than one, were used to ensure high enough larval production to ensure adequate sampling of the dispersal kernel. On three ‘control’ occasions (before the first trial, between the first and second trial, and after the second trial), we did not place colonies of B. nertina in the center of the array but still estimated settlement. The function of the control deployments was to estimate any background settlement of larvae originating from unknown colonies outside the array in order to provide greater confidence that settlers during the trial deployments originated from the colonies placed in the center of the array. In each trial deployment, settlement plates were deployed for 3 days. In the three control deployments, settlement plates were deployed for 7, 4, and 3 days, respectively. Settlers were counted within hours of retrieving the settlement plates. On each settlement plate, all settlers within a pre-defined 21.5 centimeter x 7 centimeter area (150.5 cm²) were counted under a dissecting microscope. Settlement density was standardized as the number of B. neritina per cm² per day per colony (cm^-2 d^-1 colony^-1), which assumes that the seven colonies each contributed an equal number of larvae.

BCO-DMO Processing Description:
- Adjusted field/parameter names to comply with BCO-DMO naming conventions
- Converted dates to format: YYYY-MM-DD

 

Coverage: Gulf of Mexico

NSF Award Abstract:
In marine systems, the production, dispersal, and recruitment of larvae are crucial processes that rebuild depleted adult stocks, facilitate changes in species geographic ranges, and modify the potential for adaptation under environmental stress. Traditionally, the tiny larvae of bottom-associated adults were thought to disperse far from their parents and from each other, making interactions among kin improbable. However, emerging evidence is challenging this view: larval dispersal does not always disrupt kin associations at settlement, and a large fraction of invertebrate diversity on the seafloor contains species in which most larvae disperse short distances. Limited dispersal increases the potential for interactions among kin, which has important consequences for individual fitness across many generations, and therefore the productivity of populations and the potential for adaptation. But when these consequences occur, and how exactly they manifest, remains largely unexplained. The key challenge now is to explain and predict when kin associations are likely to occur, and when they are likely to have positive or negative ecological consequences. Therefore, the key questions addressed by this research are: 1) how and when do kin associations arise and persist, and 2) what are the consequences of living with kin for survival, growth, and reproduction. This concept-driven research combines genomic approaches with experimental approaches in lab and field settings using an experimentally-tractable and representative invertebrate species. The project trains and mentors PhD students and a postdoctoral scholar at Florida State University (FSU). Field and laboratory activities are developed and incorporated into K–12 education programs and outreach opportunities at FSU.

The spatial proximity of relatives has fundamentally important consequences at multiple levels of biological organization. These consequences are likely to be particularly important in a large range of benthic marine systems, where competition, facilitation, and mating depend strongly on the proximity and number of neighbors. However, explaining and predicting the occurrence, magnitude, and direction of such effects remains challenging. Emerging evidence suggest that the ecological consequences of kin structure are unlikely to have a straight-forward relationship with dispersal potential. Therefore, it is crucial to discover new reasons for when kinship structure occurs and why it could have positive, negative, or neutral ecological consequences. This research aims to provide a new understanding of how dispersal and post-settlement processes generate spatial kin structure, how population density and relatedness influence post-settlement fitness, and how the relatedness of mating partners influences the number and fitness of their offspring (inbreeding and outbreeding). The research combines genomic approaches, experimental progeny arrays, and manipulative experiments in field and lab settings to test several hypotheses that are broadly applicable across species. By focusing on an experimentally tractable species to test broadly applicable hypotheses, the project achieves generality and a level of integration that has been difficult to achieve in previous work.