Effects of Glacial Stressors on Sperm Maturation in Colonies of the Red Tree Coral, Primnoa pacifica

The red tree coral, Primnoa pacifica, is a large, colony forming species of cold- water coral which is often an important habitat for many commercially important species of fish and crab. This keystone species is long lived and found at much shallower depths in the fjords of Glacier Bay National Park (GBNP) than elsewhere in the northern Pacific Ocean because of the phenomenon known as deep-water emergence. Due to their proximity to tidewater glaciers in GBNP, corals likely have to endure glacial stressors such as freshwater runoff and sedimentation that is not typical of populations in deeper water, which can affect physiological processes such as growth and reproduction. This study compared male colonies of Primnoa pacifica between three regions of GBNP to determine the correlation between glacial proximity and the colonies’ ability to produce fully mature spermatocytes. This study found that there is no significant difference in the size of sperm nuclei in colonies from regions at different distances from the glaciers across GBNP. This could suggest that all male colonies across the West Arm of GBNP are synchronized in their reproductive cycles due to an environmental cue that is felt across the entire fjord. Further study to determine the nature of this potential environmental cue could be valuable in understanding how climate change and warming oceans could affect populations of cold-water coral