Date of Award

Summer 6-21-2023

Degree Type


Degree Name

Doctor of Philosophy (PhD)


Ocean Science and Engineering

Committee Chair

M. Zachary Darnell

Committee Chair School

Ocean Science and Engineering

Committee Member 2

Kelly M. Darnell

Committee Member 2 School

Ocean Science and Engineering

Committee Member 3

Eric Saillant

Committee Member 3 School

Ocean Science and Engineering

Committee Member 4

Jeffery Levinton


The Atlantic sand fiddler crab, Leptuca pugilator, is found on sandy, vegetated beach across a large portion of the United States’ Atlantic and Gulf of Mexico coasts and is iconic in regions where dense populations of the species occur for its charismatic courtship, competitive, and foraging behaviors. The social dynamics of the species are complex. Reproductively active males maintain mating territories in the dangerous heat of the intertidal zone, away from their food source at the water’s edge, where they inhabit specialized mating burrows. These mating burrows are essential to successful female reproductive success, and when it is time to mate, females will move to the high intertidal to find a burrow-owning male to mate with. Males attract females with a species-specific waving display using their sexually dimorphic major claw to signal their availability. Following attraction, a female may approach a courting male and, provided the male’s burrow is of adequate quality, the two will mate within. The female will then stay below ground in the safety of the terminal chamber of the burrow throughout the oviposition and incubation process until the time comes to release her larvae. The necessity of burrow ownership in mating for males creates a high demand for territory, and males interact with one another, sometime fighting, as each mating burrow is pass down from one owner to the next. In the following pages, I address several unanswered questions concerning the nature of L. pugilator social dynamics and behavior surrounding their most important resource: the mating burrow. In Chapter II, I attempt to discern what factors differentiate territory-owning males from others who do not or cannot own territory. Chapter III is an investigation of mating burrow structure and how it changes across time and space. In Chapter IV, I address the construction of new mating burrows which is a topic that has been left largely uninvestigated at the time of this writing. Finally, Chapter V attempts to unveil the social dynamics within burrow through paternity analysis of cohabitating males and females.