Honors College

Document Type

Honors Thesis


Marine Science, Mathematics


Rhian Waller, David Hiebeler

Committee Members

Heather Hamlin, Julia Johnstone, Chris Mares

Graduation Year

December 2021

Publication Date

Fall 12-2021


Primnoa pacifica is a species of deep-sea cold-water coral that can be found in Glacier Bay National Park and Preserve in Alaska. These colonies are important to their ecosystem as they provide habitat for other species living in this area. One thing that makes P. pacifica important to study is that the species displays deep-water emergence. This is a phenomenon where species normally found in deep waters can exist in shallower waters, allowing easier access for research. The purpose of this thesis was to determine if depth effects the reproduction of male P. pacifica colonies. Two colonies from deep depths (167m and 178m) and two colonies from shallow depths (15.54m and 19.2m) were examined. The colony samples were collected from White Thunder Ridge in Glacier Bay National Park and Preserve on March 20th, 2016. Using histology methods from Waller et al. (2014), the samples were preserved, stained, cut into thin slices, and photographed. The feret nuclear diameters of spermatocytes were recorded with ImageJ and analyzed using RStudio. The results of this research determined that the male colonies at deeper depths and shallower depths are statistically similar to each other. Therefore, depth does not affect the male reproduction of the P. pacifica colonies examined. Further research with a larger sample size and colonies from other locations in Glacier Bay National Park and Preserve would expand on these results and determine if this trend is present elsewhere.