Wayne Perryman

ABSTRACT Reproductive parameters were estimated and compared for eastern North Pacific populations of common dolphins using specimen and photogrammetric data. Age and length data for Delphinus capensis and D. delphis specimens recovered as bycatch or strandings were used to estimate the postnatal growth rates needed to estimate age for calves measured in aerial photographs. Bayesian methods propagated uncertainty among models and revealed that the 2009 cohort of calves had birth dates centered on 6 March 2009 for D. capensis and 12 December 2008 for D. delphis. The evidence for discrete calving seasons suggests a mechanism of reproductive isolation has evolved between species. Photogrammetric data and Bayesian methods were also used to estimate the average length at which calves swim independently: 145.1 cm (≈ 11.1 mo) in D. capensis and 140.1 cm (≈ 14.0 mo) in D. delphis, and the proportion of calves (calves/dolphins counted): 0.045 in D. capensis and 0.069 in D. delphis. The latter parameter was converted to an index of calf production (calf/female dolphin) that was >50% lower than pregnancy rates suggesting few births occurred during the study year. Comparisons of regional differences in calf production suggest variability in habitat use patterns within the study area.

Quantifying distribution and abundance of predators is an integral part of any ecosystem monitoring effort. Antarctica poses many challenges to doing so. Recent advances in the development of Unmanned Aerial Systems (UAS), par- ticularly with vertical take-off and landing (VTOL) aircraft, have provided a new tool for addressing the challenges to estimating abundance of predators. We present preliminary results of a pilot study in the use of VTOLs for estimating abundance of krill-dependent predators. Studies in 2010/11 focused on operations, test flights, estimates of penguin abundance, comparisons to ground counts, and calculating colony area and density. Introduction Aerial photography has become a standard tool in wildlife assessments when scientists are faced with esti- mating the number of animals in large aggregations. Be- cause manned aircraft support is not always available due to cost or logistical constraints, we investigated the ap- plicability of small, unmanned aerial systems (UAS) as an alternative to manned platforms. We felt that there was an open niche for a platform that could be easily carried into the field, operated safely by a team of two people, and could collect images of adequate resolution to sup- port accurate counts of small, aggregated targets in a low contrast environment. To provide the flexibility of operat - ing in rugged terrain or from ships, we required that the aircraft be able to take off and land vertically. To reduce potential disturbance to the sampled populations and risks of pollution from fossil fuels, we restricted our search to platforms powered by batteries. We required that the UAS be capable of conducting missions under direct con- trol of the operator or through a series of predetermined waypoints. Although our primary sampling system was to be single frame images, the aircraft would be required to transmit live video to a ground station to aid in target selection and mission planning. We envisioned these sys- tems as tools for relatively short-range photographic mis- sions requiring endurance on the order of 15 - 45 minutes. After reviewing a wide range of military and commer- cial systems, we decided that the small, electric, multi-rotor copters were the best fit for our needs. These small UAS were designed to be photographic platforms and are excep- tionally stable in flight. Their control systems incorporate input from 3-axis gyros, 3-axis accelerometers, barometric altimeters, and GPS units, making them relatively easy to fly. Because the rotors on these aircraft are directly driven by electric motors and aircraft movements are controlled by simply changing the rotation rate of one of the motors, these aircraft require none of the mechanical linkages and multiple moving parts associated with standard helicopters. In addition, the use of multiple rotors reduces the size and resultant kinetic energy in each blade, making the aircraft safer for both operators and wildlife in case of a mishap. We selected Cape Shirreff, Livingston Island, South Shetland Islands for our field test because the habitat is rugged, remote, and scientists there work with large aggre- gations of penguins and fur seals. Our objectives were to: 1. Test operation of three independent verti-

This paper describes the relationship between eastern North Pacific gray whale calf production and environmental conditions in the Pacific Arctic where they feed. The results show how interannual variation in sea ice cover in the Bering and Chukchi Seas along with broader indices of North Pacific climate, such as Pacific Decadal Oscillation (PDO) and North Pacific Index (NPI), are linked to variation in gray whale reproductive output. Estimates of gray whale calf production were derived from 23 consecutive years (1994–2016) of shore‐based visual surveys conducted off California during the northward migration. PDO and NPI in combination with ice cover in the Bering and Chukchi Seas during the early phase of gestation appear to be important in explaining the observed variability in calf production. Of the 2,285 time series linear models evaluated, the model of best‐fit included PDO(July), Ice(June), NPI(February), and explained 60% of the observed variability in calf production. After...

Conventional aircraft have been used for photogrammetry studies of free-ranging whales, but are often not practical in remote regions or not affordable. Here we report on the use of a small, unmanned hexacopter (APH-22; Aerial Imaging Solutions) as an alternative method for collecting photographs to measure killer whales (Orcinus orca) at sea. We deployed and retrieved the hexacopter by hand during 60 flights (average duration 13.2 min, max 15.7 min) from the upper deck of an 8.2 m boat, utilizing the aircraft's vertical takeoff and landing (VTOL) capability. The hexacopter was quiet and stable in flight, and therefore could be flown at relatively low altitudes without disturbing whales. The payload was a Micro Four-Thirds system camera that was used to obtain 18920 still images from an altitude of 35–40 m above the whales. Tests indicated a ground-resolved distance of <1.4 cm across the full extent of a flat and undistorted field of view, and an onboard pressure altimeter en...

Vertical aerial photographs were collected of gray whales migrating along the California Coast between 1994 and 1998 to readdre ss some published findings on the biology and life history of this population based on examination of specimens. For each whale, an att empt was made to measure standard total length, the width of the whale at its widest point, the distance from the tip of the rostrum to the widest point, and the width of the flukes. For southbound gray whales, early migrants were longer on average and more likely to be parturient than those migrating later. Near-term pregnant females were wider relative to their length than other southbound gray whales. This differe nce was easily detected by visual inspection of the images and through statistical evaluation of length and width data. There was 100% agreement between identification of parturient females based on linear regression analysis of length and width and discriminate analysis of all measurements. Based on the propor...

The North Pacific right whale ( Eubalaena japonica ) was heavily exploited by both nineteenth century whaling and recent (1960s) illegal Soviet catches. Today, the species remains extremely rare especially in the eastern North Pacific. Here, we use photographic and genotype data to calculate the first mark–recapture estimates of abundance for right whales in the Bering Sea and Aleutian Islands. The estimates were very similar: photographic = 31 (95% CL 23–54), genotyping = 28 (95% CL 24–42). We also estimated the population contains eight females (95% CL 7–18) and 20 males (95% CL 17–37). Although these estimates may relate to a Bering Sea subpopulation, other data suggest that the total eastern North Pacific population is unlikely to be much larger. Its precarious status today—the world's smallest whale population for which an abundance estimate exists—is a direct consequence of uncontrolled and illegal whaling, and highlights the past failure of international management to pre...

Quantifying distribution and abundance of predators is an integral part of any ecosystem monitoring effort. Antarctica poses many challenges to doing so. Recent advances in the development of Unmanned Aerial Systems (UAS), par- ticularly with vertical take-off and landing (VTOL) aircraft, have provided a new tool for addressing the challenges to estimating abundance of predators. We present preliminary results of a pilot study in the use of VTOLs for estimating abundance of krill-dependent predators. Studies in 2010/11 focused on operations, test flights, estimates of penguin abundance, comparisons to ground counts, and calculating colony area and density. Introduction Aerial photography has become a standard tool in wildlife assessments when scientists are faced with esti- mating the number of animals in large aggregations. Be- cause manned aircraft support is not always available due to cost or logistical constraints, we investigated the ap- plicability of small, unmanned aerial s...

Gray whales in the eastern North Pacific migrate annually between summer feeding areas in the Arctic to wintering areas off Baja California, Mexico. The abundance of this whale population has been documented by shore-based counts in central California conducted by human observers searching for and recording whale sightings during the southbound migration. Here, we describe a new semi-automated system for conducting gray whale counts, and compare such to the human observer based system. This new system consists of infrared cameras which continuously monitor a fixed field of view of the ocean, automated detection software for detecting whale blows, whale-blow verification software, and counting software which estimates the number of whales that have passed by the observation station. This technology is currently being considered to support naval, oil and gas, and merchant marine operations involving marine mammals.

Estimates of cetacean abundance from transect surveys rely on unbiased estimates of group size, but estimating the size of a large school of active animals is a difficult task. To evaluate the bias and precision of estimates of dolphin group sizes, we compared estimates made from ships with counts based on aerial photographs taken from a helicopter. The analysis was based on 1,978 estimates of 366 dolphin schools in the eastern tropical Pacific, mostly schools of spotted and spinner dolphins, Stenella attenuata and S. longirostris. Estimates of group size were highly variable, both among observers for the same school and among schools for the same observer. Treating the data as a calibration problem, we developed correction factors for each of 52 observers, using the counts from the photographs, Beaufort sea state, and year as predictors. The amount and type of bias varied widely among observers, but there was a general tendency to underestimate. Before calibration, mean school size...

SUMMARY A Symposium and accompanying workshops were held in Puerto Varas, Chile from 27-29 th March 2012, to discuss recent advances in methods for non-lethal research on whales in the Southern Ocean. The first day (27 th March) was an open Symposium with invited experts who showcased new non-lethal research methods for whales in the Southern Hemisphere. The Symposium was followed by two days of Workshops that covered specific research areas. The Workshops were each one day

Unoccupied aerial systems (UAS) have become common tools for ecological monitoring and management. However, UAS use has the potential to negatively affect wildlife. Both policy makers and practitioners require data about the potential impacts of UAS on natural biota, but few studies exist and some of the published results conflict. We conducted two experiments to assess the responses of chinstrap penguins (Pygoscelis antarcticus), Antarctic fur seals (Arctocephalus gazella), and leopard seals (Hydrurga leptonyx) to UAS overflights. First, to provide a baseline for assessing disturbance from UAS operations, we compare behavioral responses from UAS flights to those from traditional, ground surveys. Second, to inform users and policy makers about preferred flight methods, we assess behavioral and physiological responses to UAS flown at specific altitudes, during different stages of breeding chronology, and with other site factors. Between January 2017 and March 2018 we conducted 268 UA...

Measurements of body size and mass are fundamental to pinniped population management and research. Manual measurements tend to be accurate but are invasive and logistically challenging to obtain. Ground-based photogrammetric techniques are less invasive, but inherent limitations make them impractical for many field applications. The recent proliferation of unmanned aerial systems (UAS) in wildlife monitoring has provided a promising new platform for the photogrammetry of free-ranging pinnipeds. Leopard seals (Hydrurga leptonyx) are an apex predator in coastal Antarctica whose body condition could be a valuable indicator of ecosystem health. We aerially surveyed leopard seals of known body size and mass to test the precision and accuracy of photogrammetry from a small UAS. Flights were conducted in January and February of 2013 and 2014 and 50 photogrammetric samples were obtained from 15 unrestrained seals. UAS-derived measurements of standard length were accurate to within 2.01 ± 1....

... Field methods During 1979, a study was conducted by the Inter-American Tropical Tuna Commission (IATTC) to investigate the accuracy and precision of observer estimates made from the tuna purse seiner, M/V Gina Anne (Allen et al., 1980). ... Estudio Gina Anne de 1979 ...

ABSTRACT Vertical aerial photographs were collected of gray whales migrating along the California Coast between 1994 and 1998 to readdress some published findings on the biology and life history of this population based on examination of specimens. For each whale, an attempt ...

ABSTRACT Dolphins leap or 'porpoise '' when sulimming fast. Hypothetical!)), there is a "crossover" speed, above which leaping is enexy saving. Field measurements indicate this speed is near 3.5 ds. Observations also shou> that when moving at high speed, dolphins can contirritr to swim long distances under uiater. a hehacior that cur- rent models of leaping-suUmming behavior had not predicted.

Aerial imagery is the most effective method National Marine Fisheries Service (NMFS) uses to assess abundance of Steller sea lions (Eumetopias jubatus). These images are traditionally captured from occupied aircraft, but the long distances between airfields along the 1900 km Aleutian Island chain, inclement weather during the survey season, and dangerous winds at sites adjacent to cliffs severely limit flying opportunities. Because of the pressing need for current trend information for a population in persistent decline we turned to a small unoccupied aircraft system (UAS), an APH-22 hexacopter. Our primary objective was to supplement traditional aerial surveys during the annual abundance survey. The second objective was to test whether the resolution of images captured with the hexacopter was adequate for sighting permanently marked individuals. From June to July 2014, NMFS biologists based on a research vessel assessed sites from Attu Island to the Delarof Islands (n = 23), survey...

ABSTRACT Reproductive parameters were estimated and compared for eastern North Pacific populations of common dolphins using specimen and photogrammetric data. Age and length data for Delphinus capensis and D. delphis specimens recovered as bycatch or strandings were used to estimate the postnatal growth rates needed to estimate age for calves measured in aerial photographs. Bayesian methods propagated uncertainty among models and revealed that the 2009 cohort of calves had birth dates centered on 6 March 2009 for D. capensis and 12 December 2008 for D. delphis. The evidence for discrete calving seasons suggests a mechanism of reproductive isolation has evolved between species. Photogrammetric data and Bayesian methods were also used to estimate the average length at which calves swim independently: 145.1 cm (≈ 11.1 mo) in D. capensis and 140.1 cm (≈ 14.0 mo) in D. delphis, and the proportion of calves (calves/dolphins counted): 0.045 in D. capensis and 0.069 in D. delphis. The latter parameter was converted to an index of calf production (calf/female dolphin) that was >50% lower than pregnancy rates suggesting few births occurred during the study year. Comparisons of regional differences in calf production suggest variability in habitat use patterns within the study area.