Chronic stress from fishing gear entanglement is recorded in baleen from a bowhead whale (Balaena mysticetus).

Here, we analyzed baleen samples for both GC hormones ( I i.e i ., immunoreactive cortisol and corticosterone and/or their metabolites) along the length of a baleen plate from an 11.1 m juvenile male bowhead whale that was severely entangled in fishing rope when it died. Immunoreactive cortisol and corticosterone were both measurable in baleen from 17B6, and baseline corticosterone concentrations were over 3-fold higher than baseline cortisol. This is consistent with other recent studies of GCs in baleen, in which corticosterone concentrations were up to 4-fold higher than cortisol in baleen (Hunt I et al i . Therefore, baseline concentration of corticosterone within baleen may be increased relative to cortisol due to its greater lipophilicity or other properties that enhance its retention within the baleen matrix. [Extracted from the article]