Dear MARMAM, My co-authors and I would like to share with you our recent publication: Mauricio Seguel, Diego Perez-Venegas, Josefina Gutierrez, Daniel E. Crocker, and Eugene J. DeRango. Parasitism elicits a stress response that allocates resources for immune function in South American fur seals (*Arctocephalus australis*) Physiological and Biochemical Zoology 92, no. 3 (May/June 2019): 326-338. The article may be reached via this link: https://doi.org/10.1086/702960 Please contact me at gderango@gmail.com if you would like to request a PDF copy. Abstract: Parasites can cause chronic stress in some animal species, and this type of stress response has been associated with adverse consequences for the host. In order to know whether parasitism elicited a stress response associated with decreased host fitness, hookworm (*Uncinaria* sp.) infection was studied in a colony of South American fur seals (*Arctocephalus australis*) in which hookworms infect nearly all pups born in a reproductive season. A parasite-free group was generated by treating a subset of pups with an antiparasitic drug before they developed patent hookworm infection. Stress and metabolic hormones, energy balance, and humoral and cellular immune parameters were measured in this group and hookworm-infected pups. Hookworms elicited a marked increase in plasma cortisol levels in fur seal pups. These hookworm-infected pups were able to maintain constant glucose levels, despite losing body mass over the course of infection potentially because of increased protein catabolism. Infected pups were able to mount an effective immune response against the parasite and eliminated hookworms from the intestine, recovering partial body mass lost as a result of hookworm infection at the end of the study period. As shown in previous studies, adequate glucose levels are critical for proper T lymphocyte reactivity, and it is possible that, through activation of a stress response, energy can be readily available for immune response against the parasite contributing to early recovery from infection. Although there are potential fitness costs to mounting a sustained stress response, these could also be adaptive and promote survival during critical life-history stages. Best regards, Geno DeRango PhD Student Galapagos Sea Lion Project Bielefeld University