Beluga, Delphinapterus Leucas, Ethogram: a Tool for Cook Inlet Beluga Conservation?
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Beluga, Delphinapterus leucas, Ethogram: A Tool for Cook Inlet Beluga Conservation? MARIAN HOWE, MANUEL CASTELLOTE, CHRISTOPHER GARNER, PAUL MCKEE, ROBERT J. SMALL, and RODERICK HOBBS Introduction and accurately (Müller et al., 1998), ing displayed by orca, Orcinus orca as well as understood in terms of their (Martinez and Klinghammer, 1978), An ethogram is a catalogue of mu- causative and functional bases (Pur- are specific to only that species. Even tually exclusive and objective behav- ton, 1978). The establishment of a ba- though an ethogram based on the be- iors or actions exhibited by an animal sic ethogram is essential to the pursuit haviors of one population is widely that avoids subjectivity and functional of further behavioral analyses of any accepted as not representative for the inference as to their possible purpose. given species (Scheer et al., 2004). species as a whole, that ethogram can It is a key tool that helps to quantify Despite the potential value of an serve as a reference and standard to species-specific behaviors by describ- ethogram to behavioral studies, only understand basic species traits and to ing the discrete, basic motor patterns a few are available for a select num- inform species management decisions. that form the behavioral repertoire of ber of species (Scheer et al., 2004). Utilizing an ethogram to study a a given species (Kikkawa and Thorne, For marine mammals, the behavior of species of concern will provide a 1971; Martin and Bateson, 2007). By which has been studied extensively, valuable tool to the emerging field of describing and defining the behavioral the lack of ethograms cataloging their “conservation behavior,” which uses inventory of a species as an ethogram, behaviors is surprising (a complete list the proximate and ultimate aspects of behaviors among different populations of studies that include cetacean etho- animal behavior to aid conservation may be compared more thoroughly grams is given in Appendix A). The decisions and reduce the loss of biodi- majority of cetacean ethograms focus versity (Buchholz, 2007). The conser- on Tursiops (e.g., Mann and Smuts, vation of cetacean species may benefit Marian Howe was with the Alaska Department 1999; von Streit et al., 2011), includ- from ethogram use, as cetaceans are of Fish and Game, 333 Raspberry Road, An- ing perhaps the most comprehensive known to exhibit behavioral changes chorage, AK 99518, and is currently with the Hawaii Institute of Marine Biology, 46-007 Lili- marine mammal ethogram, developed in response to a wide variety of anthro- puna Road, Kaneohe, HI 96744. Manuel Castel- by Müller et al. (1998), who built upon pogenic disturbances including navy lote and Roderick Hobbs are with the National Marine Mammal Laboratory, Alaska Fisheries previous observations to describe over sonar, aircraft overflight, ship traffic, Science Center, National Marine Fisheries Ser- one hundred behaviors of the bottle- ice breaking, and marine construction vice, NOAA, 7600 Sand Point Way N.E., Se- nose dolphins, Tursiops truncates, ob- (Richardson et al., 1995; Southall et attle, WA 98115-6349. Christopher Garner is with the Department of Defense, Joint-Base served along the San Diego coastline. al., 2007). In addition, the response Elmendorf Richardson, Anchorage, AK 99506. Some of the behaviors described of bowhead whales, Balaena mysti- Paul McKee is with the U.S. Fish and Wildlife in the cetacean ethograms, such as cetus, and possibly other cetaceans to Service, 1011 East Tudor Road, Anchorage, AK 99503. Robert J. Small is with the Alaska leaping, are shared among differ- these anthropogenic disturbances var- Department of Fish and Game, 1255 West 8th ent species (Norris and Dohl, 1979; ies with behavioral activity (Beale and Street, AK 99811-5526. Dudzinski, 1996; Müller et al., 1998), Monaghan, 2004; Ellison et al., 2012). doi: dx.doi.org/10.7755/MFR.77.1.3 while other behaviors, such as spray- A complete catalog of behaviors for ABSTRACT— We present the first peer-re- ity of observing specific beluga behaviors with anecdotal observations of whale ac- viewed wild beluga, Delphinapterus leucas, in Eagle Bay and Eagle River (Knik Arm, tivity in the bay, and we encourage further whale ethogram, a comprehensive descrip- Cook Inlet). Behaviors were observed and investigation to more fully explain our re- tion and definition of behavioral states and recorded from 2007 to 2011 between May sults. The explicit language used to define events exhibited by the endangered stock and December when belugas are known this beluga ethogram will facilitate a more of Cook Inlet beluga whales (CIBWs). The to forage in the study area. We found that standard approach to behavioral studies of ethogram can be used to help quantify be- CIBWs are generally more likely to travel CIBWs, provide a means to quantify the re- luga behaviors and increase the utility of fu- than mill in Eagle Bay, except when the tide sponse of CIBWs to anthropogenic activi- ture and ongoing beluga behavioral studies, is ebbing and above its midpoint, and that ties, and allow comparison among multiple in Cook Inlet and for other populations. We traveling occurred more frequently in Eagle populations. Thus, this CIBW ethogram will tested the applicability of the ethogram by River than in either the north or south sec- potentially promote innovative approach- quantitatively examining spatial, temporal, tions of the bay. The results of our quantita- es to help manage the endangered CIBW and environmental effects on the probabil- tive behavioral analysis can be compared population. 32 Marine Fisheries Review a cetacean may thus help researchers ton, 2000; Hobbs et al., 2005; Rugh et activities associated with the remedia- quantify changes in observed behavior al., 2010). It is our hope that this belu- tion of white phosphorus residues. due to different levels and types of dis- ga whale ethogram will serve as a ref- turbance for a cetacean population in- erence for future behavioral studies of Ethogram habiting an anthropogenically-altered CIBWs and other beluga populations. We developed our ethogram oppor- environment and assist in directing We also describe how CIBW behaviors tunistically from a U.S. Army moni- management efforts. vary by tide state and location within toring project of CIBWs in Eagle One endangered stock that may ben- Eagle Bay, demonstrating how the ap- Bay and Eagle River. Observations of efit from a behavior-based manage- plication of our ethogram can increase CIBWs were carried out from 2007 ment approach is the Cook Inlet stock both ecological and behavioral knowl- to 2011 between the months of May of beluga whales (Delphinapterus leu- edge of CIBWs over varying temporal and December when belugas gather cas). This small population has been and spatial scales. Such knowledge in Eagle Bay (Huntington, 2000) and geographically isolated from other be- will help direct future studies of CIB- feed in Eagle River. Observations were luga populations for over 10,000 years Ws concerning their response to hu- conducted by two or three experienced and is also the most genetically dis- man disturbances within their critical observers using 12x45 power binocu- tinct of the species (O’Corry–Crowe habitat. lars and high-powered spotting scopes et al., 1997; Laidre et al., 2000). The from the north shore at the mouth of size of the Cook Inlet beluga whale Methods Eagle River, an advantageous sur- (CIBW) population decreased by half Study Area vey location to view whales through- between 1994 and 1998, primarily due out Eagle Bay and in the mouth of the to unsustainable subsistence harvests, Cook Inlet is a tidal estuary locat- river. ed in south-central Alaska and covers and has continued to decrease by 1.6% 2 During the 2007 field season, belu- annually since 1999 (Hobbs et al., an area of approximately 20,000 km ga observation protocol followed the 2000; Hobbs et al., 2015). with 1,350 km of coastline (Rugh et ad libitum sampling technique (Alt- The geographic range of CIBWs al., 2005). Extreme tidal fluctuations mann, 1974), with general field notes has also contracted substantially over with a 9 m range result in strong cur- recorded when belugas entered Eagle the last several decades, with very few rents up to 9–10 knots and tidal bores, Bay. From these observations, multiple whales observed in lower Cook Inlet which constantly alter the shoreline beluga behaviors were initially defined during the summer months and the (Moore et al., 2000). Our CIBW be- and described. Beginning in 2008, a area of highest concentration in the havioral studies were conducted in more systematic sampling approach upper inlet near Anchorage, the largest Eagle Bay and Eagle River, which are was employed, which consisted of a city and port in Alaska (Rugh et al., located in Knik Arm, upper Cook Inlet group follow protocol and focal group 2010). The CIBW was federally listed (Fig. 1). sampling method (Altmann, 1974). as an endangered species in 2008, pri- Glacially-fed Eagle River flows Observers tracked a group of whales marily because of the lack of popula- through Eagle River Flats, a 866 ha over the course of a 20-min sampling tion recovery after regulation of the estuarine marsh on Joint-Base Elmen- period and defined the activity of the Alaska Native subsistence hunt, a rela- dorf-Richardson, before emptying into group based on the behavioral state of tively small geographic distribution, Eagle Bay. A complex interaction of the majority of whales during the pe- and concerns about long-term popu- physical forces influences the marine riod. A “group” of whales was defined lation viability (Hill and DeMaster, system of Cook Inlet, including those as the number of estimated animals 1998; NMFS1). Because very little re- exerted by a high tidal range, glacial- sufficiently close in proximity to po- search was conducted on CIBWs prior fluvial effects from multiple river in- tentially be confused with each other to their endangered listing, a dearth of puts, high degree of sedimentation, (Mann and Smutts, 1999).