Effects of Physical Dimensions on Tide Pool Diversity

1. Effects of Physical Dimensions on Tide Pool Diversity Jessica Allen, Celine Morais, Hilary Mann, Erika McLellan, and Sydney Bliss

2. Tide Pool - Community Structure • Species differ in diversity and abundance between the rocky intertidal and tide pools, largely due to the physical and biological regimes of each • Fluctuation of physical factors is smaller in tide pools that the general intertidal (allowing vertical ranges of species to extend higher) • Conversely, biological interactions (ex. grazing and predation) are intensified in tide pools

3. Communities are often patchy and somewhat unpredictable Some species are residents, some and transients, some are accidental visitors There are strong associations between a pool’s physical size and its community structure

4. Tide Pools – Physical Factors • Main factor dictating species diversity in a tide pool • Ex. temperature, salinity, wave and splash exposure, degree of shading, volume • The intensity of these is largely dictated by pool shape and depth • Fluctuate vertically, horizontally, diurnally and seasonally

5. Thus, each pool has a unique physical regime that largely determines community structure Many studies have shown that the number of species present in a pool is associated with pool depth and volume Ex. deeper pools may support more plant and invertebrate species

6. Our study attempted determine if the physical dimensions of a tide pool affect the diversity of organisms within it, as previous studies have Null hypothesis = the physical dimensions of a tide pool have no affect on species diversity within them Alternate hypothesis = the physical dimensions of a tide pool have an affect on species diversity within them

7. Methods • Measuring abiotic factors • Sampled and recorded species within quadrates or entire tide pool • Species were collected for identification

8. Results Figure 1. The effect of tide pool size on diversity at a) Indian Point and b) Green’s Point.

10. Discussion • Ho: Physical dimensions of the tide pools would have no effect on the species diversity found within these pools • Metaxas and Scheibling, 1993; Mahon and Mahon, 1994 • Area, volume, and species diversity

11. Factors that could explain discrepancies in the findings • Cold weather • Season • Sample size • Wave action and intertidal profile • Size of tide pools sampled • Omitted depths of tide pools from our calculations

12. Future Studies • Larger sample sizes • More time needed • Greater range of tide pools • Sampling at more locations • Accurate methods of measurement • Salinity and Oxygen • Gather information at different times of day and seasons • Limited due to tides