Habitat associations of sea otters during resting and feeding were investigated in Simpson Bay, Prince William Sound, Alaska during the summer months of 2001-2003. Sea otter locations collected during boat surveys were overlaid on bathymetry and sediment maps and water depth, sediment type, distance from shore, and position in the bay (peripheral vs. central) was determined for each. Logistic regression analysis was used to determine whether sea otter habitat use was non-random according to any of these habitat variables. Water depth was the most significant habitat association for feeding behavior, with the majority of feeding dives occurring in shallow water less than 20m deep. Position in the bay was the most significant habitat association for resting behavior, with more otters resting in the center of the bay. In addition, digital images taken of the sea otters during the boat surveys of 2002 and 2003 were used to examine the potential of using nose scars to photo-identify individual sea otters. Both male and female sea otters bore nose scars. Forty-five percent of all individuals encountered were considered identifiable from nose scars and a total of 114 individuals were identified. This compares favorably with the results of photo-identification studies of other marine mammals, suggesting that photo-identification may be a useful tool for the individual identification of sea otters as well.

I examined the dynamics of an endangered population of northern bottlenose whales over a 23-year period during which its prime habitat, the Gully canyon, was made a Marine Protected Area (MPA). Using mark-recapture techniques on photo-identifications I estimate a current population of 116 animals (95% CI=101-130). The population size and sex-ratio have remained stable since before the MPA designation suggesting this population is persisting. I used photo-identifications and high definition videography to examine the social organization of northern bottlenose whales, including behavioural synchrony. Relationships are highly variable; most associations are short-lived, but there are also long-term preferred associations lasting from several years (female/immature dyads) to over a decade (mature male dyads). I found little, if any, division of the social community. Synchronized breathing is common, precise, and appears to vary with behaivoural context. Although speculative, synchronized breathing might play a role the maintenance of general social relationships within this population.

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-06-23T15:46:03Z No. of bitstreams: 1 CamilaMarchetto.pdf: 6103936 bytes, checksum: 36dc3b26c7388f19f25645a5d91132af (MD5) / Made available in DSpace on 2015-06-23T15:46:03Z (GMT). No. of bitstreams: 1 CamilaMarchetto.pdf: 6103936 bytes, checksum: 36dc3b26c7388f19f25645a5d91132af (MD5) Previous issue date: 2010 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / FAPESP - Fundação de Amparo à Pesquisa do Estado de São Paulo / Estimativas de abundância populacional são consideradas importantes parâmetros ecológicos. Estudos envolvendo estes parâmetros são escassos e concentrados em regiões específicas da distribuição do boto-cinza (Sotalia guianensis). O objetivo deste estudo foi obter a estimativa da abundância populacional desta espécie em um setor do Complexo Estuarino de Paranaguá (PR) (25º22’S – 25º27’S; 48º12’W – 48º40’W). Foram realizadas saídas a campo para aplicação da técnica de fotoidentificação no período compreendido entre o inverno de 2006 e o inverno de 2008. Uma área total de 110 km² foi dividida em três subáreas menores para que cada parte selecionada fosse amostrada em um dia. Para as saídas a campo utilizou-se uma embarcação de alumínio realizando um deslocamento em zig-zag pelo estuário a fim de aumentar a chance de encontro com os grupos de botos. A fotoidentificação foi realizada com uma câmera digital reflex 35 mm, acoplada a lentes zoom de 400 mm. As fotos tomadas foram classificadas em categorias de acordo com o foco, contraste e tamanho da nadadeira dorsal em relação à distância do fotógrafo. Para a estimativa de abundância da população utilizaram-se modelos de captura-recaptura para populações fechadas. Durante o período de estudo foram realizadas 39 saídas a campo com 227 grupos de botos que variaram de dois a 100 indivíduos (média ± DP: 12,7 ± 16,6 indivíduos). Um total de 40.340 fotografias foi tomado, sendo 13.522 (33,5%) consideradas de qualidade suficiente para serem analisadas. Dentre as fotografias de excelente qualidade, 3.114 ou 23,03% foram de indivíduos que possuíam marcas conspícuas nas nadadeiras dorsais e que permitiram uma identificação individual, totalizando 109 indivíduos diferentes identificados ao longo das temporadas de estudo. A estimativa do tamanho da população variou de 200 a 441 indivíduos dependendo do modelo utilizado. Esta pode ser considerada uma estimativa mínima, visto que somente uma parte do Complexo Estuarino de Paranaguá foi amostrada neste estudo. Em vista disso, recomenda-se amostrar toda a extensão do CEP para obter a estimativa total da população local. Do mesmo modo, este dado é importante para compor o banco de informações da Área de Proteção Ambiental de Guaraqueçaba, contribuindo para o desenvolvimento de estratégias de conservação do boto-cinza e de outros recursos biológicos locais. / Population abundance estimates can be considered one of the most important ecological parameters. Studies on Guiana dolphin (Sotalia guianensis) estimates are scarce and concentrated in specific areas of its distribution. The objective of the present study was to estimate the population size of this species in a sector of the Paranaguá Estuarine Complex (PEC) (25º22’S – 25º27’S; 48º12’W – 48º40’W), state of Paraná, Brazil. Surveys were conducted to apply the technique of photo-identification from winter 2006 to winter 2008. An area of 110 km² was divided into three smaller subareas to allow each selected portion of the estuary to be surveyed in a day. Boat-based surveys followed a random zig-zag pattern in the estuary in order to maximize the chance of encountering groups of dolphins. The photoidentification was performed using a 35 mm reflex digital camera with a 400 mm zoom lens. Photographs were classified into categories according to the focus, contrast and size of the dorsal fin in relation to distance from the photographer. Capture-recapture models for closed populations were used. A total of 39 surveys was conducted and 227 groups of dolphins were recorded, ranging from two to 100 individuals (mean ± SD: 12.7 ± 16.6 individuals). A total of 40.340 photographs was taken, from which 13.522 (33.5%) were considered useful for identification purposes. A total of 3.114 (23.03%) photographs allowed individual identification, resulting in 109 individuals identified through different seasons. The estimates gathered ranged from 200 to 441 individuals depending on the selected model. This is a minimum estimate, since only a part of the Paranaguá Estuarine Complex was sampled. It is recommended to survey the whole estuarine area where dolphins can be found in order to reach an accurate estimate of the total population size. This study adds another information to the database of the Environmental Protection Area of Guaraqueçaba, contributing to the development of conservation strategies of estuarine dolphins and other local biological resources.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Estudos envolvendo estimativas de parâmetros populacionais de cetáceos baseados em dados de foto-identificação têm crescido ao longo dos anos, possibilitando estimar parâmetros como abundância, sobrevivência, probabilidade de captura e padrões de emigração. No Brasil, ainda são poucos os estudos com cetáceos que utilizam essa abordagem, contudo, eles estão aumentando, principalmente com a espécie Sotalia guianensis (van Bénéden, 1864), conhecida como boto-cinza. O objetivo desse trabalho foi estimar a sobrevivência, a probabilidade de captura, a emigração e a abundância da população de botos-cinza na Baía de Paraty (RJ; 2307S 4433W), utilizando modelos de marcação-recaptura baseados em dados de foto-identificação, entre os anos de 2005 e 2009. Os cruzeiros foram realizados entre agosto de 2005 e julho de 2009 com uma embarcação de 26 pés e motor de 200hp. As fotografias das nadadeiras dorsais foram tomadas com a utilização de uma câmera digital Canon 20D equipada com lente de zoom 100-400mm. Foram realizadas 60 saídas de campo na Baía de Paraty totalizando 172 horas de esforço no campo, sendo 72 horas de esforço fotográfico. Nas 42 saídas com observação de botos-cinza foram efetuadas 27.892 fotografias e, destas, 6.612 (23,7%) foram consideradas adequadas e utilizadas na identificação dos indivíduos de boto-cinza. Um total de 621 indivíduos foi catalogado com base em marcas permanentes na nadadeira dorsal. Os históricos individuais de captura foram analisados no programa MARK. A estimativa de sobrevivência variou de 0,82 ( 0,05) a 0,85 ( 0,05) e a probabilidade de captura variou de 0,16 ( 0,04) a 0,40 ( 0,06). O número de indivíduos marcados na população estimado pelo modelo de Jolly-Seber foi de N = 586 ( 114,66) (IC: 361-811). A proporção de animais marcados na população para o modelo de JS foi de 0,66 ( 0,03). A partir desse valor, foi possível obter uma abundância total de 884 indivíduos ( 176,8) (IC: 602-1296). A probabilidade de emigração temporária (γ``) e de permanecer fora da área (γ`) foi de 0,43 ( 0,07) e a probabilidade de captura/recaptura variou de 0,01 ( 0,01) a 0,42 ( 0,05). A probabilidade de permanência na área (1 - γ``), assim como a probabilidade de retorno da emigração temporária (1 - γ`) foi 0,57. Apesar dos movimentos significativos de indivíduos transientes, uma vez que a área amostrada é menor do que as áreas de vida que se tem estimadas para o boto-cinza, os dados indicam uma residência moderada dos botos-cinza. A abundância anual total variou de 325 para o ano de 2005 a 448 para o ano de 2009. A análise de poder determinou que seriam necessários nove anos de estudo para observar uma tendência de queda de 5% no tamanho da população. Os resultados reforçam que a Baía de Paraty abriga uma das maiores populações já estimadas para Sotalia guianensis.

Carcharias taurus is listed as Critically Endangered along the east coast of Australia and there is concern about their status globally. The use of traditional tag–recapture methods to monitor the east coast C. taurus population have been discontinued due to tag–biofouling and injuries that relate to tag attachment. In the current study, captive and wild C. taurus were used to assess whether spots present on their flanks were suitable natural tags for individual shark recognition. Photographic images of seven captive sharks taken at monthly intervals for 13 months and at three years after the start of the study indicated that their spot number, position and relative size did not change over this period. Similarly, eighty–nine wild sharks photographically re–identified at least 23 months after their initial identification (and in one case after 14 years) confirmed long–term spot–pattern retention. Photographic recaptures of individual C. taurus provided information about their temporal and spatial distribution and movement patterns along the Australian east coast in relation to maturity, sex and reproductive condition. A total of 930 sharks were photo–identified between 2004 and 2008 at 23 aggregation sites between Wolf Rock and Montague Island. Of these, 479 were females (271 mature, 208 immature) and 452 were males (288 mature, 60 sub–adults, 104 juveniles). The distribution of pregnant C. taurus was seasonally and temporally distinct from all other sharks. Visibly pregnant C. taurus were recorded at Wolf Rock (the most northern site) from February until October, although many sharks left during July. Pregnant C. taurus were also observed at North Moreton Island, Flat Rock and Fish Rock between June and November. Resting (mature, non–gravid) females and mature males were mostly observed at mid–southern sites from December to June, with northern counts increasing from June to November. The majority of immature sharks were recorded at mid–southern sites. Of 930 sharks identified between 2004 and 2008, 149 were identified at more than one site. On average, mature females moved 338 km (SD ± 465), mature males 340 km (SD ± 299), immature females 147 km (SD ± 98), sub–adult males 185 km (SD ± 216), and juvenile males 271 km (SD ± 237). The maximum rate of movement per day was 18.5 km for a mature female shark, 20.7 km for a mature male, 4.3 km for an immature female, 86 km for a sub–adult male and 4 km for a juvenile male. Mature males and mature non–pregnant females tended to move north from mid–winter and mate in late spring/early summer in warmer waters. From about mid–winter, pregnant females began to move from the warmer waters of their gestation areas to cooler southern waters to pup (probably from late spring to mid–summer). The movement patterns of immature sharks varied temporally, and were more limited spatially. Underwater censuses, photo–identification and acoustic tracking of individual C. taurus were used to investigate their reproductive periodicity, localised movements and behavioural segregation at Wolf Rock – the most northerly aggregation site on the east Australian seaboard. A biennial reproductive cycle was indicated for 18 of 28 females for which re–identifications spanned at least two mating and/or pregnancy events. Nine of the 28 sharks appeared to exhibit a triennial reproductive cycle. Male C. taurus were observed between July and January, but were absent between February and April. Scuba divers reported seeing some mating scars on individuals from mid–October, however fresh mating scars were predominately observed on photographs of individual C. taurus taken in November and December. Four acoustically–tagged mature female sharks remained within 500 m of the Wolf Rock aggregation site within a marine sanctuary zone for 78 – 90 % of the 11–15 day study period. A minimum population estimate of 930 individuals is provided from all sharks identified between 2004 and 2008. In addition, a Jolly–Seber (open model design) mark–recapture analysis on data obtained during four scheduled photo–identification surveys (conducted between July 2006 and February 2008 at 25 aggregation sites along the east coast of Australia) was used to estimate the size of this population. A maximum of 272 sharks (143 females and 129 males) were identified during any scheduled survey period. Model averaging across the highest rated JS models (Popan data formulation) resulted in an estimate of 756 males (95% CI = 590 – 922) and 1185 females (95% CI = 901 – 1469). The mark–recapture abundance estimate is considered preliminary and requires further model development to incorporate the heterogeneity in distribution and migration patterns within the C. taurus population. The occurrence of retained fishing gear and gear–related jaw injuries were quantified from the four scheduled photo–identification surveys along the east coast of Australia. A total of 673 sharks were identified with 119 occurrences of retained fishing gear or jaw injury recorded from 113 individual sharks. For sharks that were known by spot–patterns on both flanks, 29 % of females and 52 % of males were seen with retained fishing gear or a gear–related jaw injury. The largest numbers of identified sharks (222) during the surveys were seen at Fish Rock (off the New South Wales coast): 48 % of all sharks identified with retained fishing gear were first identified at this site. Fish Rock is a designated critical habitat for C. taurus, but most forms of line fishing, except fishing while anchored or moored with bait and/or wire trace line are permitted. Results from the surveys clearly demonstrated that C. taurus is susceptible to a large variety of fishing gear and fishing methods. Current protection measures for C. taurus appear insufficient at this site, particularly as large aggregations that include immature and mature sharks occur consistently throughout the year.

This project describes a portion of a long-term study of the behavioral ecology of sea otters. Sub-studies of this project include the development of an individual recognition program for sea otters, the construction of male sea otter activity and energy budgets, and the assessment of male sea otter territory quality. The Sea Otter Nose Matching Program, or "SONMaP", was developed to identify individual sea otters in Simpson Bay, Prince William Sound, Alaska, using a blotch-pattern recognition algorithm based on the shape and location of nose scars. The performance of the SONMaP program was tested using images of otters collected during the 2002-03 field seasons, and previously matched by visually comparing every image in a catalog of 1,638 animals. In 48.9% of the visually matched images, the program accurately selected the correct image in the first 10% of the catalog. Individual follows and instantaneous sampling were used during the summers of 2004-06, to observe male sea otter behavior. Six behaviors (foraging, grooming, interacting with other otters, patrolling, resting, and surface swimming) were observed during four time periods (dawn, day, dusk, night) to create 24-hr activity budgets. Male sea otters spent 27% of their time resting, 26% swimming, 19% grooming, 14% foraging, 9% patrolling and 5% interacting with other otters. Field Metabolic Rate (FMR) was estimated by combining the energetic costs for foraging, grooming, resting, and swimming behaviors of captive otters from Yeates et al. (2007) with these activity budgets. "Swimming" accounted for the greatest percentage (43%) of energy expended each day followed by grooming (23%), resting (15%), feeding (13%) and other (5%). With a peak summer sea otter density of 5.6 otters km-2, the low percentage of time spent foraging indicates that Simpson Bay is below equilibrium density. Territory quality was assessed for male sea otters using four attributes: territory size, shoreline enclosure, accessibility, and number of females observed feeding in each territory. Each attribute was coded with a score of 0-2, and total quality scores ranged from 0.14-1.96 (0.9 + 0.61 SD). High quality territories had large areas, moderate shoreline enclosure, high accessibility, and many foraging females.

The western population of gray whales (Eschrichtius robustus) is endangered with approximately 130 individuals remaining. Many individuals return annually to the same feeding sites off northeastern Sakhalin Island, indicating a site-specific dependence to this geographic area. This apparently critically important habitat is especially vital for nursing females and their calves, as female energetic requirements are increased during lactation, and calves need to be ready to separate and begin to feed on their own. This study focuses on movements, respirations and behavioral patterns of mother/calf pairs on their feeding ground, with data collected during summer-autumn of 2002-2009. Shore-based observations included three methods: theodolite tracking, focal-animal behavior sampling, and photo-identification. Whales were categorized as three groups of individuals: mother/calf pairs, weaned calves, and other individuals. Analyses were performed to assess differences between groups of individuals, and in relation to their behavior. The null hypothesis of the study was that there were no differences in movement/respiration/behavioral patterns and habitat use between different groups of individuals. Results did not support this hypothesis. Significant differences in movements and respirations were found for certain groups of individuals. These differences also varied in relation to the whales' behavioral activity (feeding, feeding/traveling, and traveling). The shore-based photography was used to obtain additional information on individuals (especially mother/calf pairs) and their sightings, as well as to evaluate the success of this approach. A total of 144 individuals, including 10 females (sighted with calves) and 31 calves were identified during 2004-2009. The shore-based photo-identification approach was successful, and due to being a non-invasive technique, is recommended as a supplemental approach to vessel-based photo-ID efforts. Reproductive success and survival of western gray whales are concern especially due to the presence of industrial activity in the area, as well as recently increased mortalities of female gray whales off Japan. Therefore, the results of this study indicate the importance of considering differences in needs and habitat utilization of different groups of individuals for basic science information as well as for management purposes of protection of western gray whales.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Estudos envolvendo estimativas de parâmetros populacionais de cetáceos baseados em dados de foto-identificação têm crescido ao longo dos anos, possibilitando estimar parâmetros como abundância, sobrevivência, probabilidade de captura e padrões de emigração. No Brasil, ainda são poucos os estudos com cetáceos que utilizam essa abordagem, contudo, eles estão aumentando, principalmente com a espécie Sotalia guianensis (van Bénéden, 1864), conhecida como boto-cinza. O objetivo desse trabalho foi estimar a sobrevivência, a probabilidade de captura, a emigração e a abundância da população de botos-cinza na Baía de Paraty (RJ; 2307S 4433W), utilizando modelos de marcação-recaptura baseados em dados de foto-identificação, entre os anos de 2005 e 2009. Os cruzeiros foram realizados entre agosto de 2005 e julho de 2009 com uma embarcação de 26 pés e motor de 200hp. As fotografias das nadadeiras dorsais foram tomadas com a utilização de uma câmera digital Canon 20D equipada com lente de zoom 100-400mm. Foram realizadas 60 saídas de campo na Baía de Paraty totalizando 172 horas de esforço no campo, sendo 72 horas de esforço fotográfico. Nas 42 saídas com observação de botos-cinza foram efetuadas 27.892 fotografias e, destas, 6.612 (23,7%) foram consideradas adequadas e utilizadas na identificação dos indivíduos de boto-cinza. Um total de 621 indivíduos foi catalogado com base em marcas permanentes na nadadeira dorsal. Os históricos individuais de captura foram analisados no programa MARK. A estimativa de sobrevivência variou de 0,82 ( 0,05) a 0,85 ( 0,05) e a probabilidade de captura variou de 0,16 ( 0,04) a 0,40 ( 0,06). O número de indivíduos marcados na população estimado pelo modelo de Jolly-Seber foi de N = 586 ( 114,66) (IC: 361-811). A proporção de animais marcados na população para o modelo de JS foi de 0,66 ( 0,03). A partir desse valor, foi possível obter uma abundância total de 884 indivíduos ( 176,8) (IC: 602-1296). A probabilidade de emigração temporária (γ``) e de permanecer fora da área (γ`) foi de 0,43 ( 0,07) e a probabilidade de captura/recaptura variou de 0,01 ( 0,01) a 0,42 ( 0,05). A probabilidade de permanência na área (1 - γ``), assim como a probabilidade de retorno da emigração temporária (1 - γ`) foi 0,57. Apesar dos movimentos significativos de indivíduos transientes, uma vez que a área amostrada é menor do que as áreas de vida que se tem estimadas para o boto-cinza, os dados indicam uma residência moderada dos botos-cinza. A abundância anual total variou de 325 para o ano de 2005 a 448 para o ano de 2009. A análise de poder determinou que seriam necessários nove anos de estudo para observar uma tendência de queda de 5% no tamanho da população. Os resultados reforçam que a Baía de Paraty abriga uma das maiores populações já estimadas para Sotalia guianensis.

In 1938 Dr. Eugene Gudger concluded of the Red Sea that "whale sharks must surely abound in this region." Seventy years later, multi-method research began on a whale shark (Rhincodon typus) aggregation at Shib Habil, a reef near Al Lith, Saudi Arabia. However, in 2017 and 2018, a dramatic decline in encounters at this site drew questions about the aggregation's future and overall whale shark population trends in the region. In this dissertation, I describe and discuss the two-year decline in encounters and show that neither remotely sensed sea surface temperature nor chlorophyll-a concentrations were significantly different in seasons with or without sharks. Citizen science-based photo identification was used to characterize the northern Red Sea population, the Red Sea population as a whole, show limited crossover within the basin, and connections with another aggregation in Djibouti. Scarring rates within the Red Sea are compared to recent global studies, and the Red Sea uniquely had no predator bites observed, suggesting boat collisions are likely the leading cause of major scars. Finally, building upon previous genetic work comparing Red Sea and Tanzanian sharks using microsatellites, the mitochondrial control region was sequenced, and two global haplotype networks were produced and compared to each other and previous work. The stability of genetic diversity within the Shib Habil aggregation is compared to declines previously measured in Australia. As tourism develops along the northern Saudi Arabian coast and citizen science increases in the Red Sea, population dynamics within the region could be better understood. The genetic connectivity of Red Sea whale sharks to the Indo-Pacific population exemplifies the need for continued collaborative research beyond local aggregations and multinational conservation measures.

Heaviside‟s dolphins, Cephalorhynchus heavisidii, are among the least known cetaceans. They are endemic to the coastal waters along the west coast of southern Africa. The occurrence, behaviour and group dynamics were investigated for these dolphins in Table Bay, South Africa during the summer of 2008 and 2009. Markrecapture photographic identification techniques, modelling techniques and Geographical Information System (GIS) were used to analyse the data. The dolphins were observed primarily in a well-defined 7 km2 area on the south side of Table Bay along a 3 km east-west stretch of coast known as Granger Bay, and within 2 km from shore. They used this area heterogeneously; for the array of behaviours observed, all core areas (50 % kernels) were located in Granger Bay with very little overlap of areas used for milling, socialising, resting and travelling. Milling and socialising were exhibited more often than travelling and resting. Foraging was never observed in areas close to shore, which supports earlier studies suggesting that these dolphins forage primarily offshore. Of the 95 identified individuals, 24.2 % of the individuals were seen only once and 73.7 % of the individuals were sighted less than five times while two individuals were seen 11 times. Groups varied in size from one to 26 animals with a median of five animals. Many of the potential dyads were never seen and those observed had generally weak measure of association. The group structure appears highly dynamic, with great lability in group sizes and membership, suggesting a fluid social system with mostly weak inter-individual bonds. Individuals in Table Bay display low site fidelity, at least in the short-term. The observed pattern of area use and behavioural preferences indicate that coastal management strategies should consider the ecological and behavioural needs of Heaviside's dolphins to appropriately safeguard this species as a valuable component of South African natural treasures and legally protected taxa. Further continuing research is needed to build on this initial study to better understand the processes that shape the population structure and group dynamics of Heaviside's dolphins, and to provide further detail on habitat preferences and areas used, both in Table Bay and environs. / Dissertation (MSc)--University of Pretoria, 2011. / Zoology and Entomology / Unrestricted