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Koski W.R.,LGL Ltd | Abgrall P.,LGL Ltd | Yazvenko S.B.,Second Street
Journal of Cetacean Research and Management | Year: 2010

A literature review, internet searches and communications with personnel working with unmanned aerial systems (UAS) were used to identify the capabilities of UAS throughout the world. We assessed their ability to replace manned aerial surveys for marine mammals,sea turtles and seabirds and to monitor, in real time, sea ice and other physical features that might influence marine mammal distribution. The vast majority of the systems identified were either too expensive or their capabilities did not meet minimum standards necessary to perform the tasks required of them in real time. Eight systems were identified that might be able to perform some of the desired tasks. Several other systems had similarcapabilities but had not been tested or would require upgrades. Installation of high-definition (HD) video and better stabilisation systems would improve UAS performance. It is recommended that development of HD video with real-time data transmission and improved stabilisation systems for UAS be pursued and that side-by-side comparisons of a few of the best systems be conducted.

Reurink F.,Wageningen University | Reurink F.,Simon Fraser University | Hentze N.,LGL Ltd | Rourke J.,Hemmera Envirochem Inc. | And 2 more authors.
Behavioral Ecology | Year: 2016

Many studies have investigated how foraging behavior such as prey choice varies with factors such as prey size or density. Models of such relationships can be applied "in reverse" to translate easily observed foraging behaviors into assays of habitat attributes that cannot (easily) be measured directly. One such model analyzes the speed of a forager flying between patches, where it captures prey. Faster flight shortens the travel time and hence elevates the intake rate, but is increasingly expensive. The model shows that the net intake rate is maximized at the point at which the energetic cost of flight is equivalent to the net rate of intake. Easy-to-measure flight speeds can thus be translated into hard-to-measure foraging intake rates using established flight power relationships. We studied nonbreeding Pacific dunlins (Calidris alpina pacifica) at 4 intertidal sites on the Fraser River estuary, British Columbia, Canada. These sites differed sufficiently that we expected food availability and hence the attainable foraging rate to differ. We measured interpatch flight speeds of dunlins foraging along the tideline within each site. The measured ground speed, calculated airspeed, and the statistically derived zero-wind effect airspeed all differed significantly between sites, matching in rank order our expectation of habitat quality based on their physical differences. Intake rate estimates ranged from 4.10 W (best mudflat) to 3.48 W (poorest). We think it unlikely that we would have been able to find such small differences using direct measures of foraging intake. © 2015 The Author.

Carroll E.L.,University of Auckland | Childerhouse S.J.,Australian Antarctic Division | Christie M.,Oregon State University | Lavery S.,University of Auckland | And 6 more authors.
Molecular Ecology | Year: 2012

The identification and characterization of reproductively isolated subpopulations or 'stocks' are essential for effective conservation and management decisions. This can be difficult in vagile marine species like marine mammals. We used paternity assignment and 'gametic recapture' to examine the reproductive autonomy of southern right whales (Eubalaena australis) on their New Zealand (NZ) calving grounds. We derived DNA profiles for 34 mother-calf pairs from skin biopsy samples, using sex-specific markers, 13 microsatellite loci and mtDNA haplotypes. We constructed DNA profiles for 314 adult males, representing 30% of the census male abundance of the NZ stock, previously estimated from genotypic mark-recapture modelling to be 1085 (95% CL 855, 1416). Under the hypothesis of demographic closure and the assumption of equal reproductive success among males, we predict: (i) the proportion of paternities assigned will reflect the proportion of the male population sampled and (ii) the gametic mark-recapture (GMR) estimate of male abundance will be equivalent to the census male estimate for the NZ stock. Consistent with these predictions, we found that the proportion of assigned paternities equalled the proportion of the census male population size sampled. Using the sample of males as the initial capture, and paternity assignment as the recapture, the GMR estimate of male abundance was 1001 (95% CL 542, 1469), similar to the male census estimate. These findings suggest that right whales returning to the NZ calving ground are reproductively autonomous on a generational timescale, as well as isolated by maternal fidelity on an evolutionary timescale, from others in the Indo-Pacific region. © 2012 Blackwell Publishing Ltd.

Swan K.D.,University of Victoria | Hawkes V.C.,LGL Ltd | Gregory P.T.,University of Victoria
Herpetological Conservation and Biology | Year: 2015

Hydropower is the largest source of renewable energy in the world, yet relatively little is known about how dams and their operations influence terrestrial and semi-aquatic wildlife. We evaluated the impact of annual reservoir inundation on breeding Columbia Spotted Frogs (Rana luteiventris) and Western Toads (Anaxyrus boreas) in the drawdown zone of Kinbasket Reservoir in British Columbia, Canada. During spring and summer of 2010 and 2011, we conducted visual encounter surveys at 40 ponds in the drawdown zone to document the reproductive phenology of these species relative to the timing of reservoir inundation. We used a negative binomial regression to identify characteristics associated with R. luteiventris breeding activity (measured by number of egg masses located) in ponds in the drawdown zone. Pond elevation, mean temperature, mean pH, and presence of fish were all positively correlated with the number of R. luteiventris egg masses in a pond. These results point to a preference for breeding ponds that promote rapid larval development and/or those that are least frequently inundated by the reservoir. We emphasize that proposed hydroelectric developments and changes to existing reservoir operation regimes should recognize the importance of amphibian breeding habitat in drawdown zones. © 2015. Kelly D. Swan. All Rights Reserved.

Carroll E.,University of Auckland | Patenaude N.,LGL Ltd | Alexander A.,University of Auckland | Alexander A.,Oregon State University | And 8 more authors.
Marine Ecology Progress Series | Year: 2011

During the last 2 centuries, southern right whales Eubalaena australis were hunted to near extinction, and an estimated 150 000 were killed by pre-industrial whaling in the 19th century and illegal Soviet whaling in the 20th century. Here we focus on the coastal calving grounds of Australia and New Zealand (NZ), where previous work suggests 2 genetically distinct stocks of southern right whales are recovering. Historical migration patterns and spatially variable patterns of recovery suggest each of these stocks are subdivided into 2 stocks: (1) NZ, comprising NZ subantarctic (NZSA) and mainland NZ (MNZ) stocks; and (2) Australia, comprising southwest and southeast stocks. We expand upon previous work to investigate population subdivision by analysing over 1000 samples collected at 6 locations across NZ and Australia, although sample sizes were small from some locations. Mitochondrial DNA (mtDNA) control region haplotypes (500 bp) and microsatellite genotypes (13 loci) were used to identify 707 individual whales and to test for genetic differentiation. For the first time, we documented the movement of 7 individual whales between the NZSA and MNZ based on the matching of multilocus genotypes. Given the current and historical evidence, we hypothesise that individuals from the NZ subantarctic are slowly recolonising MNZ, where a former calving ground was extirpated. We also suggest that southeast Australian right whales represent a remnant stock, distinct from the southwest Australian stock, based on significant differentiation in mtDNA haplotype frequencies (FST = 0.15, p < 0.01; ΦST = 0.12, p = 0.02) and contrasting patterns of recovery. In comparison with significant differences in mtDNA haplotype frequencies found between the 3 proposed stocks (overall FST = 0.07, ΦST = 0.12, p < 0.001), we found no significant differentiation in microsatellite loci (overall FST = 0.004, G′ST = 0.019, p = 0.07), suggesting ongoing or recent historical reproductive interchange. © Inter-Research 2011.

Carroll E.L.,University of Auckland | Patenaude N.J.,University of Auckland | Patenaude N.J.,LGL Ltd | Childerhouse S.J.,Australian Antarctic Division | And 4 more authors.
Marine Biology | Year: 2011

The abundance of New Zealand subantarctic southern right whales (Eubalaena australis) was estimated for the first time using mark-recapture methods based on photo-identification and microsatellite genotyping (13 loci). Individual identification photographs of 383 whales and microsatellite genotypes of 235 whales were collected during annual austral winter field surveys from 1995 to 1998. Given the 4-year survey period and lack of geographic and demographic closure, we estimated super-population abundance using the POPAN Jolly-Seber model implemented in the software programme MARK. Models with constant survivorship but time-varying capture probability and probability of entry into the population were the most suitable due to the survey design. This provided estimates of abundance in 1998 of 908 non-calf whales (95% C. L. = 755, 1,123) for the photo-identification and 910 non-calf whales (95% C. L. = 641, 1,354) for the microsatellite genotype data sets. The current estimate of 900 whales may represent less than 5% of the pre-whaling abundance in New Zealand waters. © 2011 Springer-Verlag.

Robertson F.C.,University of British Columbia | Robertson F.C.,LGL Ltd | Koski W.R.,LGL Ltd | Trites A.W.,University of British Columbia
Marine Ecology Progress Series | Year: 2016

Aerial surveys are sometimes used to assess the densities of wide-ranging whales, as well as changes in their distributions in response to human activity. Such surveys also provide data used to estimate numbers of animals exposed to different received levels of seismic sound, as required by regulators. However, estimates of abundance are often biased because they fail to account for the effects of seismic operations on the surfacing and diving behavior of whales. Our objective was to determine the extent to which analyses of the distribution of bowhead whales Balaena mysticetus are affected by changes in visual 'availability' caused by seismic operations. We used aerial survey data collected during seismic operations in the Alaskan Beaufort Sea from late August to early October 2008 and fit spatial density surface models to bowhead sighting data to predict whale density in an ensonified area. We also incorporated availability correction factors to determine the sensitivity of density estimates to changes in surfacing and diving behavior caused by seismic operations. The influence of altered whale behavior was then evaluated by comparing a series of realistic simulated scenarios in which models incorporated undisturbed or seismic disturbance-related correction factors. Results suggest that the numbers of bowhead whales present in the vicinity of seismic operations during the bowhead autumn migration are underestimated if the behavioral effects of seismic operations on whales are ignored. Our study highlights the importance of accounting for changes in whale behavior that can affect sightability when estimating numbers and distribution of whales in the vicinity of industrial activity. © 2016 SAMS.

Donaldson M.R.,University of British Columbia | Raby G.D.,Carleton University | Nguyen V.N.,Carleton University | Hinch S.G.,University of British Columbia | And 11 more authors.
Canadian Journal of Fisheries and Aquatic Sciences | Year: 2013

We evaluate the utility of an inexpensive, portable recovery bag designed to facilitate recovery of fish from capture stress by combining physiological assays, biotelemetry, and social science surveys. Adult migrating Pacific salmon (Oncorhynchus spp.) were used as a model, since some of their populations are threatened. While catch-and-release is common, there is a need to ensure that it is sustainable. A social science survey revealed that anglers generally have positive attitudes towards recovery bag use, particularly if research identifies that such techniques could be effective. Physiological assays on pink salmon (Oncorhynchus gorbuscha) revealed benefits of both highand low-velocity recovery, but high velocity was most effective with reduced plasma cortisol concentrations and similar plasma sodium and chloride concentrations as those found in controls at all recovery durations. A biotelemetry study on sockeye salmon (Oncorhynchus nerka) captured by anglers and stressed by air exposure then placed in recovery bags had 20% higher, but not significantly different, survival than no-recovery salmon. The integration of natural science and social science provides an important step forward in developing methods for promoting recovery of fish from capture.

Donaldson M.R.,University of British Columbia | Hinch S.G.,University of British Columbia | Patterson D.A.,Simon Fraser University | Hills J.,Simon Fraser University | And 7 more authors.
Fisheries Research | Year: 2011

Few studies have examined the effects of fisheries capture on wild fish, particularly in the context of evaluating the sustainability of capture and release methods for Pacific salmon (Oncorhynchus spp.) during upriver migration. This study examined the physiological condition, post-release behaviour and survival of adult migrating sockeye salmon (O. nerka) in the Fraser River, British Columbia, Canada. Fish were captured by either beach seine or angling and released immediately, or were captured by angling and released following a 24-h recovery period in a net pen. Before release, all salmon were biopsied or tagged with radio telemetry transmitters. Capture by either angling or beach seine with immediate release resulted in >95% survival 24. h after release, whereas net pen recovery after angling resulted in ∼80% survival. This differential in survival was similarly expressed in the percentage of released fish reaching natal sub-watersheds, with 52.2% and 36.3% of fish immediately released by beach seine and angling reaching natal sub-watersheds, respectively, compared with 2.9% of fish released after angling and net pen recovery. Blood plasma stress indices reflected the 10-fold difference in survival, with a ∼4-fold higher plasma cortisol, a ∼2-fold higher plasma glucose and significantly depressed plasma ions and osmolality relative to fish sampled upon capture. Plasma lactate did not differ among groups. Collectively, these results suggest that a 24. h recovery in net pen following angling failed to promote post-release survival experienced with immediate release after angling or beach seining. © 2010 Elsevier B.V.

PubMed | University of British Columbia, LGL Ltd and University of California at Davis
Type: Journal Article | Journal: Conservation physiology | Year: 2016

Transformation of earths ecosystems by anthropogenic climate change is predicted for the 21st century. In many regions, the associated increase in environmental temperatures and reduced precipitation will have direct effects on the physiological performance of terrestrial and aquatic ectotherms and have already threatened fish biodiversity and important fisheries. The threat of elevated environmental temperatures is particularly salient for members of the

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