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Accurate and precise estimates of the timing of whisker growth and shedding are necessary to interpret biochemical information stored in whiskers. This fine-scale examination of harbor seal (Phoca vitulina Linnaeus, 1758) whisker growth and shedding identified an asymptotic growth pattern with initial rapid growth that decays over time that can be defined with the von Bertalanffy curve. Initial growth rates were similar among whiskers, but estimated growth coefficients (K) and asymptotic lengths ([L.sub.[infinity]]) differed by follicle positions suggesting that differences in total whisker lengths result from dissimilarly shaped growth curves. In other words, longer whisker length is attained by delaying the growth rate decay. There was substantial intra-and interseal variation in shedding dates; whisker shedding began at the caudal margin of the whisker bed and progressed toward the nose. Shedding of marked whiskers from the three study seals took from 78 to 133 days; however, selecting whiskers only from the most caudal follicle of the bottom three rows constrained the period of whisker shedding to 7-43 days. These differences in growth and shedding of harbor seal whiskers emphasize the importance of considering follicle position to select whiskers that are the most similar for analyses of information stored in whiskers. Key words: whisker, vibrissa, growth rates, Phoca vitulina, harbor seal Des estimations exactes et precises du moment de la croissance et de la chute des vibrisses sont necessaires pour interpreter l'information biochimique qu'elles recelent. Le present examen a echelle fine de la croissance et de la chute des vibrisses de phoques communs (Phoca vitulina Linnaeus, 1758) revele un motif de croissance asymptotique presentant une croissance initiale rapide ralentissant au fil du temps qui peut etre definie avec la courbe de von Bertalanffy. Les taux de croissance initiaux sont semblables pour les differentes vibrisses, mais les coefficients de croissance (K) et longueurs asymptotiques ([L.sub.[infinity]]) estimes varient selon la position du follicule, ce qui indiquerait que les differences de longueur totale des vibrisses resultent de courbes de croissance de formes differentes. Autrement dit, une plus grande longueur des vibrisses est atteinte en retardant la diminution du taux de croissance. La date de chute des vibrisses varie considerablement pour un meme phoque et d'un phoque a l'autre; la chute des vibrisses commence a la marge caudale des moustaches et progresse vers le nez. La chute de vibrisses marquees des trois phoques etudies a pris de 78 a 133 jours, mais seulement de 7 a 43 jours en ce qui concerne uniquement les vibrisses du follicule le plus caudal des trois rangees inferieures. Ces differences de la croissance et de la chute des vibrisses de phoques communs soulignent l'importance de tenir compte de la position du follicule dans la selection de vibrisses les plus semblables analyser l'information qu'elles recelent. [Traduit par la Redaction] Mots-cles : moustache, vibrisses, taux de croissance, Phoca vitulina, phoque commun, Introduction Analysis of serial sections of biologically inert tissues can be used to create a timeline of biochemical information related to the ecology and physiology of free-ranging organisms. Several compounds [...]

Alaska's Cook Inlet beluga whales, Delphinapterus leucas, an endangered species, were estimated by the National Marine Fisheries Service, NOAA, at a mere 312 animals in 2012. Understanding the habitat use and defining critical habitat for these whales is crucial for their conservation. The Little Susitna River Delta is thought to be an important summer foraging, mating, and calving habitat area for the species. To investigate the efficiency of new methodologies and increase our understanding of habitat use, the Alaska SeaLife Center initiated the Cook Inlet beluga whale remote monitoring pilot study in the summer of 2011 using video monitoring. Observers used two remotely controlled video cameras mounted on a 9 m tower approximately 1.5 river miles from the confluence of the Little Susitna River and the waters of Cook Inlet. Belugas were observed through the cameras from May to August 2011 as they entered the river mouth and traveled upstream past the camera site. The remotely captured behavioral information in this secluded location added finer-scale information about habitat use and behavior to the existing body of knowledge about Cook Inlet belugas. Behaviors observed and video-recorded included typical beluga behaviors (e.g., travelling, milling, and suspected feeding) along with a higher-than-anticipated occurrence of other behaviors (e.g., breaching, spyhopping, mother/ newborn interactions). Additionally, detailed group composition, distribution, and duration of sighting data was collected, proving both the effectiveness and value of this monitoring method., Introduction In 1979, Alaska's Cook Inlet beluga whale, Delphinapterus leucas, population was estimated to be 1,300 animals (Calkins'). Abundance surveys in the early 1990's indicated a 47% decline, and in [...]