Seahorses (Hippocampus sp.) are known to be vulnerable species due to threats, such as habitat loss or over-harvesting, that can lead to a rapid decline in wild populations. Additionally, the life history traits of seahorses, including their limited home ranges and low mobility, are also factors that can lead to declines. The primary objectives of this study were to document seasonal population dynamics and analyze morphological variation in the dwarf seahorse, Hippocampus zosterae. Fish were collected from Tampa Bay, Fl, photographed, and released back into the wild over an entire year from August 2022 through July 2023. Our results indicate seasonal patterns in seahorse abundances, with the largest population numbers reported in October 2022 during the peak breeding season, which is supported by the increase in juveniles observed in November 2022. Seahorse abundances declined as seagrass blades shortened during the winter months with populations rebounding during the early summer. Photos of the fish were analyzed using the program ImageJ with seahorses measured (mm) based on snout length, head length, trunk length, tail length, body width, and total body length. Our preliminary results concluded that trunk length, tail length, and body width were found to be sexually dimorphic in adult dwarf seahorses from our yearlong study. These morphological differences across the sexes could be attributed to the unique reproductive roles in seahorses due to male pregnancy. Ongoing analyses are being conducted to determine if the cirri appendages, which are theorized to aid in camouflaging and potential mating preferences, on the seahorses are also sexually dimorphic. Preliminary results indicate a seasonal difference in cirri presence. The results from this study will have a significant impact on the understanding of population dynamics for conservation monitoring, identifying habitat changes in the seagrass beds, and detecting wild seahorse mating patterns and preferences.

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