Abstract: The collection of blood spots on filter paper for hormone analysis has become quite popular in human and primate studies, mostly because of the ease of handling, storage, and transportation of samples, but has never been tested in wild marine mammals. In this paper, we describe a protocol for the collection of blood spots and the analysis of cortisol in southern elephant seal (Mirounga leonina) weanlings. We demonstrated that cortisol measured in blood spots is very well correlated to cortisol measured in serum samples, and we calculated equations to convert between the two. We describe the possible pitfalls of the blood spot analysis protocol, and suggest solutions. The use of blood spots for hormone analysis presents many advantages for field research, may open interesting opportunities like the serial sampling of unrestrained adult individuals, and represents a step towards the reduction of invasiveness of hormone studies.
Key Words: Cortisol, blood spots, filter paper, southern elephant seal, Mirounga leonina, Falkland Islands
Document Type: Research article
Page Numbers: 251-256