Author: Roderick C. Hobbs Publisher: ISBN: Category : Aerial surveys in wildlife management Languages : en Pages : 25
Book Description
"Measuring population trends, and detecting a change in the trend, of Cook Inlet beluga whales (CIB), Delphinapterus leucas, has a specific role in the co-management agreement that determines harvest levels, and a more general application in the management of the population. Currently, an annual aerial survey schedule has provided abundance estimates from which growth trends for this population are determined. Under the harvest co-management agreement, the measured trend over a 10-year period is used to classify the population into one of three growth categories ('high', 'intermediate', or 'low'; Appendix). The growth category, along with the average abundance over the last 5-year period, is used to determine the number of takes allowed over the next 5-year hunting period (Appendix). For a more general application, we would like to be able to detect a change in the growth rate of the population that results from a change in the underlying life history parameters such as birth interval and rates of survival and identify the year that the change occurred"--Introduction.
Author: Roderick C. Hobbs Publisher: ISBN: Category : Aerial surveys in wildlife management Languages : en Pages : 25
Book Description
"Measuring population trends, and detecting a change in the trend, of Cook Inlet beluga whales (CIB), Delphinapterus leucas, has a specific role in the co-management agreement that determines harvest levels, and a more general application in the management of the population. Currently, an annual aerial survey schedule has provided abundance estimates from which growth trends for this population are determined. Under the harvest co-management agreement, the measured trend over a 10-year period is used to classify the population into one of three growth categories ('high', 'intermediate', or 'low'; Appendix). The growth category, along with the average abundance over the last 5-year period, is used to determine the number of takes allowed over the next 5-year hunting period (Appendix). For a more general application, we would like to be able to detect a change in the growth rate of the population that results from a change in the underlying life history parameters such as birth interval and rates of survival and identify the year that the change occurred"--Introduction.
Author: Kim E. W. Shelden Publisher: ISBN: Category : Aerial surveys in wildlife management Languages : en Pages : 62
Book Description
The National Marine Fisheries Service (NMFS) has conducted aerial surveys to estimate abundance of the beluga population in Cook Inlet, Alaska, each June, July, or both from 1993 to 2012, after which biennial surveys began in 2014. The current document presents survey results and subsequent analyses yielding an abundance estimate and population trend based on data collected during June 2016. Surveys occurred May 31 - June 9, 2016 (49.2 flight hours). All surveys were flown in twin-engine, high-wing aircraft (i.e., an Aero Commander) at a target altitude of 244 m (800 ft) and speed of 185 km/hour (100 knots), consistent with NMFS' surveys of Cook Inlet conducted in previous years. Tracklines were flown 1.4 km from the shoreline, along the entire Cook Inlet coast, including islands. Additionally, sawtooth pattern tracklines were flown across the inlet in 2016. These aerial surveys effectively covered 40% of the total surface area of Cook Inlet and 100% of the coastline. In particular, most of the upper inlet, north of the East and West Foreland where beluga whales are consistently found, was surveyed seven times (out of seven attempts). Paired, independent observers searched on the coastal side of the plane, where most beluga sightings occur, while a single observer searched on the inlet side. A computer operator/data recorder periodically monitored distance from the shoreline (1.4 km) with a clinometer (angle 10°). After finding beluga groups, a series of aerial passes allowed all observers to each make independent counts of every group. In addition, whale groups were video recorded for later analysis and more precise counts in the laboratory. [doi:10.7289/V5/AFSC-PR-2017-09 (https://doi.org/10.7289/V5/AFSC-PR-2017-09)]
Author: Kim E. W. Shelden Publisher: ISBN: Category : Aerial surveys in wildlife management Languages : en Pages : 122
Book Description
The National Marine Fisheries Service (NMFS) has conducted aerial surveys of the beluga population in Cook Inlet, Alaska, each June and/or July since 1993. Results from 1993 to 2000 and 2001 to 2004 were published previously. The current document is a compilation of data from field reports for the subsequent years, from 2005 to 2012. Surveys during these year occurred 31 May-9 June 2005 (54.5 flight hours), 6-15 June 2006 (58.4 flight hours), 7-15 June 2007 (47.2 flight hours), 3-12 June 2008 (47.7 flight hours), 2-9 June 2009 (39.4 flight hours), 1-10 June 2010 (48.4 flight hours), 31 May-9 June 2011 (47.0 flight hours), and 29 May-7 June 2012 (53.0 flight hours). All surveys were flown in twin-engine, high-wing aircraft (i.e., an Aero Commander or Twin Otter) at a target altitude of 244 m (800 ft) and speed of 185 km/hour (100 knots), consistent with NMFS' surveys of Cook Inlet conducted in previous years. Tracklines were flown 1.4 km from the shoreline, along the entire Cook Inlet coast, including islands. Offshore transects were designed to run the length of Cook Inlet or in a sawtooth pattern across the inlet, minimizing overlap within each season, as well as between years. These aerial surveys effectively covered 25% to 34% of the total surface area of Cook Inlet in each of the 8 years and nearly 100% of the coastline (with the exception of 2007: 71%). In particular, most of the upper inlet, north of the Forelands where beluga whales are consistently found, was surveyed five to six times each year. Paired, independent observers searched on the coastal side of the plane, where virtually all beluga sightings occur, while a single observer searched on the offshore side. A computer operator/data recorder periodically monitored distance from the shoreline (1.4 km) with a clinometer (angle 10°). After finding beluga groups, a series of aerial passes allowed all four observers to each make four or more independent counts of every group, (i.e., typically 16 counts of each group conducted during 8 passes). In addition, whale groups were video recorded for later analysis and more precise counts in the laboratory. During the 8 years of surveys from 2005 to 2012, belugas were not seen in lower Cook Inlet (south of East and West Foreland) nor in the upper inlet south of North Foreland and Point Possession until 2012 when a group of at least seven belugas was observed headed toward West Foreland on 31 May. Before 1996, it was common to see beluga groups south of North Foreland in Trading Bay. Since the mid-1990s to early 2000s, only one or two beluga groups have been found in lower Cook Inlet south of East and West Foreland and none in the region between the Forelands and North Foreland. Groups of more than one or two whales have not been seen in the lower inlet since 1995. During the 2012 survey, this beluga group moved into the upper inlet and was observed in Trading Bay for the remainder of the survey (highest median count = 21 whales). The annual sums of medians from aerial counts provide a quick index of relative abundance, not corrected for estimates of whales missed and assuming there may be some exchange of whales between areas. Annual index counts from 2005 to 2012 (192, 153, 224, 126, 303, 291, 208, and 319, respectively) included the lowest (2008) and highest (2012) counts recorded since surveys began in 1993 (1993-2004 counts: 302, 276, 322, 287, 261, 192, 217, 184, 210, 181, 174, and 187).
Author: Kim E. W. Shelden Publisher: ISBN: Category : Mammal surveys Languages : en Pages : 226
Book Description
Cook Inlet beluga whales, Delphinapterus leucas, are currently listed as 'Endangered' under the U.S. Endangered Species Act (ESA). The National Marine Fisheries Service (NMFS) began monitoring this population during the 1990s after it was added to the ESA Candidate Species list in 1988. Monitoring efforts included aerial surveys, and in 1995, the first attempts to capture and satellite-tag whales. Working with Canadian scientists and Alaska Native subsistence hunters in 1995 and 1997, tagging methods were adapted to conditions in Cook Inlet (muddy water, extreme tides, and extensive mudflats), culminating in successful capture and tracking of a whale during the summer of 1999. This was followed by three more years of capture and tagging studies during late summer. Tags were attached to 18 whales between 1999 and 2002. We do not have detailed accounts of these later tagging seasons (e.g., similar to the Appendix chronicling events from the 1997 and 1999 seasons in Ferrero et al. (2000)). Litzky et al. (2001) summarized field operations for the 2000 tagging season, but no reports exist for 2001 and 2002. A reanalysis of the tag dataset (Goetz et al. 2012) led to questions about the captures and how tags were programmed during this time period. Given the Cook Inlet population has continued to decline (Hobbs et al. 2015, Shelden et al. 2017), and was listed as an Endangered Distinct Population Segment under the ESA in October 2008 (NOAA 2008), future recommendations for tagging will depend on lessons learned from these past projects. Lacking detailed field reports, we consolidated information from multiple sources. Herein, we bring these varied sources together to provide a thorough documentation of the tagging operations undertaken in Cook Inlet each summer in 2000, 2001, and 2002. We include revised tag transmission timelines, monthly movement maps, dive behavior data, and ice-association graphs and maps for all whales (where applicable) tagged in 1999, 2000, 2001, and 2002. Whale locations were compared to sighting records (opportunistic and systematic) to determine how many whales were likely proximate to tagged whales. Animations of whale movements are available at http://www.afsc.noaa.gov/News/Cook_Inlet_Beluga_Range_Contracted.htm (accessed 17 Aug. 2016). Beginning with the 2000 season, each whale underwent a health assessment at the time of tagging. Results from laboratory analyses of the blood, blubber, skin, and mucus samples are presented. These include results obtained for hematology and serum chemistry values, hormones, DNA extractions, blubber lipid composition, fatty acid profiles, stable isotope ratios, and persistent organic pollutant profiles. We also provide a follow-up to the tagging study, describing captured and tagged whales that have been photo-documented since 2005 by the Cook Inlet Beluga Whale Photo-identification Project (https://www.cookinletbelugas.com/).
Author: Stephanie A. Norman Publisher: ISBN: 9781267662675 Category : Languages : en Pages :
Book Description
Cook Inlet, Alaska belugas (CIB) (Delphinapterus leucas) are a genetically and geographically isolated wild stock, residing in the upper Inlet's waters year-round. This small, declining population was listed as endangered in 2008. Relatively little research has been conducted on diseases and environmental threats to this stock that may play a role in their decline and long-term viability. To date, impacts of disease, anthropogenic drivers, and environmental factors on population dynamics have not been well characterized. Four studies were conducted to help evaluate CIB health and survival threats: 1) characterization of hematology and serum chemistry values in Bristol Bay belugas (BBB), a healthy growing population, for comparison to CIB, 2) characterization of hematology and serum chemistry variation patterns from captive belugas over 22 years, to provide methods applicable to wild populations such as CIB, 3) development of a model using anthropogenic and environmental factors to demonstrate CIB population trajectories based on survival and fecundity rates in a simulated population, and 4) evaluation of fecal pathogens and contributing fecal host sources to surface waters and sediment in areas of upper CI that overlap critical beluga habitat. Results from the first study showed that mean hematocrit, chloride, creatinine, total protein (TP), albumin, and alkaline phosphatase were significantly lower in May than they were in September, whereas mean corpuscular hemoglobin concentration, monocytes, phosphorous, magnesium, blood urea nitrogen, alanine transaminase, aspartate aminotransferase, gamma glutamyl transferase, and creatinine kinase were significantly higher. Mean TP, white blood cell count, neutrophils, and lymphocytes were significantly higher early in the capture period than they were later. No significant differences in blood analyte values were noted between males and females. Usingoverall body length as a proxy for age, larger (older) belugas had lower white blood cell, lymphocyte, and eosinophil counts as well as lower sodium, potassium, and calcium levels but higher creatinine levels than smaller belugas. In this study, the most striking differences in analyte values for BBB were seasonal, and the analyte value variability noted for age and sex was similar to that seen in other studied wild beluga populations. Based on bloodwork values, BBB appeared to adapt to capture and handling. The BBB bloodwork established useful baselines for further monitoring of this population and future comparisons to BBB. Results from the second study, in which blood analyte variation was evaluated in a captive beluga population, demonstrated that many blood analytes differed based on whale sex and age. For many blood analytes, similar circannual variation patterns were observed across facility location, and seasonal variation was also observed. These findings from a long-term assessment of individual analyte variation in healthy cetaceans agree with previous reports that many blood analytes differ significantly between partitioning factors such as age groups and seasons. Age, seasonality, and sex were important determinants for a majority of the blood analytes, therefore, the variability of these variables should be accounted for when investigating health trends over time. The use of an age-structured population model to assess the impact of stressors on CIB fecundity and survival demonstrated that decreases in fecundity probability had a smaller effect on population growth compared to decreases in survival probability, for the same magnitude of modification. Results furthermore suggested that supplementing census data with age-structured modeling can improve the detection and projection of changes in survivorship and fecundity of endangered populations. The results from study three demonstrated an efficient and non-invasive method to help determine the magnitude of a stressor that would likely result in the observed decline of the CIB population that could also be applied to other populations. In addition, the results can identify hypothetical causes of the decline and what stressors justify additional resources for study. In the last study, determining fecal pathogen pollution patterns and sources, the most common host source fecal marker was human source, followed by the livestock marker that may also represent large wildlife hosts such as moose and deer. The prevalence of Giardia was greater than that for Cryptosporidium, overall and by matrix type. Salmonella was not detected. Vibrio was more prevalent in sediment than in water for both months. Norovirus was detected in water samples but not in sediment. The most prevalent fecal host source marker detected overall was human, followed by livestock. Human-host Bacteroidales marker prevalence was greatest in water both months, followed by livestock in water and canine and avian in sediment. Fecal coliform counts in surface waters were within Alaska water quality standards, and were 10-100x greater in sediment. In unadjusted regression analyses, water was found more likely to be positive for either protozoal organism compared to sediment. In the final study, the greatest contribution of tested fecal host-specific markers appeared to be from human sources. Exposure of belugas to pathogens in waters where they most often congregate and socialize should be a consideration. In addition, exposure of marine life and humans to potential fecal pathogens may be influenced by climatic and anthropogenic factors and should be considered when evaluating fecal monitoring programs. Findings from these studies will contribute to current knowledge of CIB health and aid conservation policy in terms of: management of endangered species; the integration of wildlife conservation with population health interventions; and applicability to other endangered or threatened marine life.
Author: Roderick C. Hobbs Publisher: ISBN: Category : White whale Languages : en Pages : 29
Book Description
Beluga whales (Delphinapterus leucas) in Cook Inlet, Alaska, form an isolated, depleted population that is now listed as endangered. One monitor of population health is through documenting calving rates. This study provides an index of the number of calves seen in Cook Inlet in August. Although the August survey is the focus for the calf index, given most births are thought to occur by late July, data collected during the annual June abundance survey are used for comparison. Analyses cover the period from 2006 to 2010 (a feasibility and techniques study occurred in August 2005). Systematic aerial surveys covered primary habitat for belugas in Cook Inlet, and paired video cameras provided images used in laboratory analysis. A total of 44 groups of whales from the August surveys were examined, of which most contained images of calves that were identified by color (darker than adults), small size, and proximity to adults. Among these whale groups, 688 usable images were found and examined. By rating inter-whale proximity in five categories, and estimating the ages represented, we developed criteria for recognizing young calves, an index that represents primarily young-of-the-year calves, and a second index that represents young-of-the-year, yearling calves, and some young juveniles. It appears that more calves were born in 2006 (12%) than in subsequent years (2007-2010 ranged from 0.5% to 3%). However, these calving rates have several potential biases and should be used for trend analysis only, not for absolute estimates of calf production. Overall, the 5-year average (2006-2010) birth rate was 3.6%. With mortality rates per year of roughly 3% or more (based on counts of beach-cast carcasses), this would suggest that the birth rate estimated here is probably at or below the replacement level necessary for recovery of this population.
Author: Kristin L. Laidre Publisher: ISBN: Category : White whale Languages : en Pages : 33
Book Description
The following report contains detailed information on the movement patterns of beluga whales that were satellite-tagged in 1999 and 2000 in Cook Inlet, Alaska. The seasonal movements and dive patterns of three whales CI-9901, CI-0001, and CI-0002 were analyzed, and movement data from the whales tagged in 2000 were referenced to in a subsequent paper by Hobbs et al. (2005). However, the detailed analyses of diving behavior and movement patterns of these individual whales were never made available until now. The seasonal movements and dive patterns of three belugas in Cook Inlet, Alaska, were monitored between June and January 1999-2000 using satellite telemetry. One adult male whale was tagged on 30 May 1999 and tracked until 16 September 1999 (109 days), and one juvenile female and one adult male were tagged on 13 September 2000 and tracked until 2 (115 days) and 18 January 2001 (124 days), respectively. Whales remained in the inlet the entire time they were tracked. Mean dive depths across the entire tracking period ranged from 2.6 m (SD = 5.2) to 5.2 m (SD = 8.8). Mean dive durations ranged from 1.4 minutes (SD = 2.0) to 3.1 minutes (SD = 4.1). Overall mean time at surface (between 0 and 1 m) ranged from 23% to 70% and appeared to be related to season and location. Behavioral periods were identified for each whale (4-60 days) based on stationary movements in a particular part of the inlet and unique diving behavior during that time. Significant differences were found between diving behavior and tidal rate of change and direction, as well as whale location and average sea-ice concentration. Belugas in Cook Inlet display seasonal variation in dive behavior and movement patterns, both of which have implications for sightings rates, correction factors, and abundance estimates obtained for the population. [doi:10.7289/V5AFSC-PR-2017-08 (https://doi.org/10.7289/V5/AFSC-PR-2017-08)].
Author: Roderick C. Hobbs
Author: Roderick C. Hobbs
Author: Kim E. W. Shelden
Author: 
Author: Kim E. W. Shelden
Author: Kim E. W. Shelden
Author: 
Author: Stephanie A. Norman
Author: Roderick C. Hobbs
Author: Kristin L. Laidre