Possible effects of climate change on the populations of Galapagos pinnipeds

The future of Galapagos Sea Lion Zalophus wollebaeki and Galapagos Fur Seal Arctocephalus galapagoensis populations was evaluated with reference to a conservative model of predicted climate change. Populations of both species will decrease during strong El Niño events and disease outbreaks will likely increase. Fur Seals may be exposed to a high risk of extinction if thermocline depth increases during extended warming events, since they can feed only near the surface and depend on upwelling. While predictions of the oceanographic conditions around Galapagos for the next 50 years remain uncertain, the combination of climate change and other human-induced threats (disease, disturbance, massacres and pollution) increases the need for conservation measures to protect these animals and their ecosystem

Humpback whale song revolutions continue to spread from the central into the eastern South Pacific

Funding: COCIBA grants of USFQ National Geographic Society - W396-15; NERC Sea Mammal Research Unit - NE/R015007/1; Project CETACEA Ecuador Royal Society - NF140667, UF160081; Rufford Foundation.Cultural transmission of behaviour is an important aspect of many animal communities ranging from humans to birds. Male humpback whales (Megaptera novaeangliae) sing a repetitive, stereotyped, socially learnt and culturally transmitted song display that slowly evolves each year. Most males within a population sing the same, slow-evolving song type; but in the South Pacific, song ‘revolutions’ have led to rapid and complete replacement of one song type by another introduced from a neighbouring population. Songs spread eastwards, from eastern Australia to French Polynesia, but the easterly extent of this transmission was unknown. Here, we investigated whether song revolutions continue to spread from the central (French Polynesia) into the eastern (Ecuador) South Pacific region. Similarity analyses using three consecutive years of song data (2016–2018) revealed that song themes recorded in 2016–2018 French Polynesian song matched song themes sung in 2018 Ecuadorian song, suggesting continued easterly transmission of song to Ecuador, and vocal connectivity across the entire South Pacific Ocean basin. This study demonstrates songs first identified in western populations can be transmitted across the entire South Pacific, supporting the potential for a circumpolar Southern Hemisphere cultural transmission of song and a vocal culture rivalled in its extent only by our own.Publisher PDFPeer reviewe

Blood gases, biochemistry and haematology of Galápagos hawksbill turtles (Eretmochelys imbricata)

The hawksbill turtle, Eretmochelys imbricata, is a marine chelonian with a circum-global distribution, but the species is critically endangered and has nearly vanished from the eastern Pacific. Although reference blood parameter intervals have been published for many chelonian species and populations, including nesting Atlantic hawksbills, no such baseline biochemical and blood gas values have been reported for wild Pacific hawksbill turtles. Blood samples were drawn from eight hawksbill turtles captured in near shore foraging locations within the Galápagos archipelago over a period of four sequential years; three of these turtles were recaptured and sampled on multiple occasions. Of the eight sea turtles sampled, five were immature and of unknown sex, and the other three were females. A portable blood analyzer was used to obtain near immediate field results for a suite of blood gas and chemistry parameters. Values affected by temperature were corrected in two ways: (i) with standard formulas and (ii) with auto-corrections made by the portable analyzer. A bench top blood chemistry analyzer was used to measure a series of biochemistry parameters from plasma. Standard laboratory haematology techniques were employed for red and white blood cell counts and to determine haematocrit manually, which was compared to the haematocrit values generated by the portable analyzer. The values reported in this study provide reference data that may be useful in comparisons among populations and in detecting changes in health status among Galápagos sea turtles. The findings might also be helpful in future efforts to demonstrate associations between specific biochemical parameters and disease or environmental disasters

Análisis de la fidelidad de sitio entre machos y hembras de ballenas jorobadas que visitan las costas de Esmeraldas (Ecuador)

Humpback whales (Megaptera novaeangliae) migrate across the world’s oceans from feeding grounds in polar waters in high latitudes to breeding grounds in tropical waters. Although this species is predictable in its areas of occurrence, there are several poorly understood aspects of its migration patterns. This study aims to evaluate the differences between site fidelity of male and female humpback whales off the coast of Esmeraldas (Ecuador) for the years 2010, 2011 and 2012. A total of 57 whale skin samples were obtained using a biopsy system. For sex determination, primers SFY1204 and SFY0097 were used. A variable section of the mitochondrial DNA control region (D-loop) was amplified by PCR and sequenced to identify haplotypes. Of the humpback whale samples analyzed, it was found that 12 corresponded to females and 44 to males, and a total of 23 different haplotypes were identified. Molecular variance analysis (AMOVA) showed that males had higher site fidelity, although a significant difference was found in the haplotype frequency and nucleotide composition between males within the 2010 and 2011 seasons. These differences were not found within the seasons of 2010-2012 and 2011-2012, which can be attributed to the fact that samples of 2010 were collected in August, when males are in resident groups, while samples of 2011 were collected in July when most males can be in transit to breeding areas further north in Costa Rica and Panama. In addition, females showed no significant differences in haplotype frequency and nucleotide composition, although between female humpback whales of the 2010 and 2012 seasons, only one haplotype was shared. These results may be due to the relatively small number of female samples. These findings may suggest that although male humpback whales disperse in the tropical breeding ground from Southern Ecuador to Northern Costa Rica, they return each year to their native breeding ground. On the other hand, females probably remain in feeding sites during alternate years, to recover from the energy expenditure of gestation and lactation.La ballena jorobada (Megaptera novaeangliae) migra en todos los océanos del mundo desde sus zonas de alimentación en aguas polares a zonas de reproducción en aguas tropicales. Aunque esta especie es predecible en sus áreas de ocurrencia, son aún poco conocidos varios aspectos de la migración de la ballena jorobada. El presente trabajo tuvo como objetivo evaluar las diferencias de fidelidad de sitio entre machos y hembras de ballenas jorobadas que visitaron las costas de Esmeraldas (Ecuador) durante las temporadas 2010, 2011 y 2012. Un total de 57 muestras de piel de ballena se obtuvieron mediante un sistema de toma de biopsias. Para la determinación del sexo se utilizó los primers SFY1204 y SFY0097. Una sección variable de la región control del ADN mitocondrial (D-loop) se amplificó mediante PCR y secuenció para analizar los haplotipos presentes. De las muestras de ballenas jorobadas analizadas se determinó que 12 correspondieron a hembras y 44 a machos, y se identificó un total de 23 haplotipos diferentes. Al realizar un análisis de varianza molecular (AMOVA), se encontró que los machos presentaban una mayor fidelidad de sitio, a pesar de una diferencia notable en la frecuencia de haplotipos y composición de nucleótidos entre machos de las temporadas 2010 y 2011. Esta diferencia no se encontró entre las temporadas 2010-2012 ni 2011-2012, posiblemente porque las muestras del 2010 fueron recolectadas en Agosto, cuando los machos se quedan en grupos residentes, mientras que las muestras del 2011 fueron recolectados en Julio cuando la mayoría de machos están en tránsito hacia áreas de reproducción en el norte como Panamá y Costa Rica. Las hembras no mostraron diferencias significativas en la frecuencia de haplotipos y composición de nucleótidos, a pesar de que en las hembras de las temporadas 2010 y 2012 se compartió un solo haplotipo. Estos resultados, pueden deberse al limitado número de muestras de ballenas jorobadas hembras. Estos hallazgos pueden sugerir que a pesar de que las ballenas jorobadas machos se dispersan desde las zonas de reproducción al sur del Ecuador hasta el norte de Costa Rica, regresan cada año a su zona de reproducción originaria. Por otro lado, las hembras posiblemente permanecen en años alternos en los sitios de alimentación para recuperarse de los gastos energéticos de la gestación y lactancia

Blood Gases, Biochemistry, and Hematology of Galapagos Green Turtles (Chelonia Mydas)

The green turtle, Chelonia mydas, is an endangered marine chelonian with a circum-global distribution. Reference blood parameter intervals have been published for some chelonian species, but baseline hematology, biochemical, and blood gas values are lacking from the Galapagos sea turtles. Analyses were done on blood samples drawn from 28 green turtles captured in two foraging locations on San Cristóbal Island (14 from each site). Of these turtles, 20 were immature and of unknown sex; the other eight were males (five mature, three immature). A portable blood analyzer (iSTAT) was used to obtain near immediate field results for pH, lactate, pO2, pCO2, HCO3−, Hct, Hb, Na, K, iCa, and Glu. Parameter values affected by temperature were corrected in two ways: (1) with standard formulas; and (2) with auto-corrections made by the iSTAT. The two methods yielded clinically equivalent results. Standard laboratory hematology techniques were employed for the red and white blood cell counts and the hematocrit determination, which was also compared to the hematocrit values generated by the iSTAT. Of all blood analytes, only lactate concentrations were positively correlated with body size. All other values showed no significant difference between the two sample locations nor were they correlated with body size or internal temperature. For hematocrit count, the iSTAT blood analyzer yielded results indistinguishable from those obtained with high-speed centrifugation. The values reported in this study provide baseline data that may be useful in comparisons among populations and in detecting changes in health status among Galapagos sea turtles. The findings might also be helpful in future efforts to demonstrate associations between specific biochemical parameters and disease

Humpback whales interfering when mammal-eating killer whales attack other species: mobbing behavior and interspecific altruism?

Humpback whales (Megaptera novaeangliae) are known to interfere with attacking killer whales (Orcinus orca). To investigate why, we reviewed accounts of 115 interactions between them. Humpbacks initiated the majority of interactions (57% vs. 43%; n=72), although the killer whales were almost exclusively mammal-eating forms (MEKWs, 95%) vs. fish-eaters (5%; n=108). When MEKWs approached humpbacks (n=27), they attacked 85% of the time and targeted only calves. When humpbacks approached killer whales (n=41), 93% were MEKWs, and >87% of them were attacking or feeding on prey at the time. When humpbacks interacted with attacking MEKWs, 11% of the prey were humpbacks and 89% comprised 10 other species, including 3 cetaceans, 6 pinnipeds, and 1 teleost fish. Approaching humpbacks often harassed attacking MEKWs (>55% of 56 interactions), regardless of the prey species, which we argue was mobbing behavior. Humpback mobbing sometimes allowed MEKW prey, including nonhumpbacks, to escape. We suggest that humpbacks initially responded to vocalizations of attacking MEKWs without knowing the prey species targeted. Although reciprocity or kin selection might explain communal defense of conspecific calves, there was no apparent benefit to humpbacks continuing to interfere when other species were being attacked. Interspecific altruism, even if unintentional, could not be ruled out

Blood gases, biochemistry and haematology of Galápagos marine iguanas ( Amblyrhynchus cristatus )

The marine iguana, Amblyrhynchus cristatus, is an iconic lizard endemic to the Galápagos Islands of Ecuador, but surprisingly little information exists on baseline health parameters for this species. We analysed blood samples drawn from 35 marine iguanas captured at three locations on San Cristóbal Island. A portable blood analyser (iSTAT) was used to obtain near-immediate field results for pH, lactate, partial pressure of O2, partial pressure of CO2, bicarbonate (HCO3−), percentage O2 saturation, haematocrit, haemoglobin, sodium, potassium, ionized calcium and glucose. Parameter values affected by temperature were auto-corrected by the iSTAT. Standard laboratory haematology techniques were employed for differential white blood cell counts and haematocrit determination; resulting values were also compared with the haematocrit values generated by the iSTAT. Body temperature, heart rate, respiratory rate and body measurements were also recorded. Body length was positively correlated with several blood chemistry values (HCO3− and glucose) and two haematology parameters (haemoglobin and manually determined haematocrit). A notable finding was the unusually high blood sodium level; the mean value of 178 mg/dl is among the highest known for any reptile. This value is likely to be a conservative estimate because some samples exceeded the maximal value the iSTAT can detect. For haematocrit determination, the iSTAT blood analyser yielded results significantly lower than those obtained with high-speed centrifugation. The values reported in this study provide baseline data that may be useful in comparisons among populations and in detecting changes in health status among marine iguanas affected by natural disturbances or anthropogenic threats. The findings might also be helpful in future efforts to demonstrate associations between specific biochemical parameters and disease

Estado del manatí del Amazonas (Trichechus inunguis) en la Reserva Cuyabeno, Ecuador

Amazonian manatees live in black water rivers and lakes in the Amazon basin. A study of Amazonian manatees in the Cuyabeno Reserve conducted by Timm et al. [1] in 1983 gave first information on distribution of manatees in the Cuyabeno Reserve and they sug­gested a possible extinction of the Amazonian Manatee in the following decade. Here I present results of observations, and interviews, realized 13 years after the first study as complementary observations during a research project on Amazon River dolphins (Inia geoffrensis) from 1996 to 1999. We surveyed during more than 127 days covering about 6.175km in manatee habitat with more than 456 hours continuously observing black water rivers and lagoons and we carried out manatee surveys paddling in the Lagunas Grandes de Cuyabeno. Interviews with tour guides, park rangers and native Indians give a complete sighting list for the presence of manatees and insight into the current situation in the Re­serve. The relative abundance of manatees in the Cuyabeno River is 0.01 animals/h effort and even less in the Lagartococha River with 0.007 animals/h effort. Populations in the Lagartococha River seem to be severely reduced. Hunting in both rivers continued despite legal protection with 16 manatees killed from 1995 to 1998. Overall 40 to 49 animals were seen in the Cuyabeno Reserve from 1996 to 1998. Even though, predictions that manatees would be extinct by 1993 were not fulfilled, they are rare in the Reserve and living in a protected area does not necessarily safeguard this species.Los manatíes amazónicos viven en ríos de aguas negras y lagunas de la Cuenca Amazónica. La primera información sobre la distribución y el estado de conservación de manatíes en la Reserva Cuyabeno proviene de un estudio realizado en 1983 por Timm y otros [1]. Ellos concluyeron que el manatí se puede extinguir en la próxima década. En este artículo se presenta los resultados de observaciones y entrevistas realizados desde 1996 a 1999, trece años después. Durante 127 días de monitoreo del Delfín Amazónico (Inia geoffrensis) en el habitat del manatí a lo largo de ríos y lagunas de agua negra, se observó durante 456 horas. Adicionalmente se realizaron monitoreos dirigidos a manatíes en las Lagunas Grandes de Cuyabeno. Entrevistas con guías de turismo, guardaparques e indígenas dan una lista completa de avistamientos de manatíes, su distribución y la situación de conservación. La abundancia relativa estimada en el Río Cuyabeno es de 0,01 animales/hora de esfuerzo y aün menor en el río Lagartococha con 0,007 animales/ hora de esfuerzo. Las poblaciones en el rio Lagartococha parecen severamente reducidas. En ambos ríos la caza entre 1995 y 1998 continuó. A pesar de la protección legal se mataron al menos 16 animales dentro de la Reserva Cuyabeno, por ende el hecho de vivir en una area protegida no necesariamente significa la sobrevivencia de la especie

Densidad poblacional, estimaciones de abundancia, preferencia de hábitat y la estructura social de los delfines del Río Amazonas (Inia geoffrensis) en la Reserva Cuyabeno, Ecuador

Population density, abundance, habitat preference, home range and social structure of Amazon River dolphins or Boto (Inia geoffrensis) were studied in the Cuyabeno Reserve in Ecuador from 1996 to 1998. The study area the Cuyabeno and Lagartococha Rivers are two blackwater tributaries, to the Aguarico River a white ater river. While the Cuyabeno river is flowing through tierra firme forest with numerous oxbow lakes on the 111km stretch surveyed, the Lagartococha river was surveyed on 86,7kms passing through varzea. The maximum population density of 0.39 Botos/km river is fairly low in comparison to other study areas in the lower Amazon basin and depends significantly on season and habitat. Most animals tend to be close to the river mouth during the low water season and in Lagoons with Igapó and Grasslands during the high water season. Behaviour was most divers in Lagoons with Igapó and Grasslands, while shallow river sections with beaches are only used as migration passages. Although Botos are considered solitary animals, observations in the Cuyabeno Reserve confirm a high amount of groups from two to eight animals with calves living in groups of three or four animals rather than mother calf pairs. According to Photo ID studies, home range of Botos in the Cuyabeno Reserve extended over different rivers and travelling distances of more than 200kms within the Lagartococha to the Cuyabeno River were recorded. However, most of the dolphins identified according to natural marks on their dorsal fin or back, remained within 50kms, which shows overlapping home ranges of different groups or single animals.La densidad poblacional, abundancia y preferencia de hábitat del delfín Amazónico o Boto (Inia geoffrensis) en la Reserva Cuyabeno, Ecuador fue estudiado entre 1996 y 1998. El área de estudio se ubicó en el río Cuyabeno y en el río Lagartococha, dos tributarios de aguas negras los cuales desembocan al rio Aguarico. El río Cuyabeno en sus 111 km estudiados fluye a través de bosques de tierra firme con numerosas lagunas meandricas, mientras que el río Lagartococha a lo largo de los 86,7 km que fueron estudiados se encuentra en un sistema de bosques inundados. La máxima densidad poblacional de 0,39 Botos/km río es bastante bajo en comparación con otras áreas de estudio de la Amazonía baja y depende significativamente de la estación del año y el hábitat. En la época seca, la mayoría de los animales tienden a mantenerse cerca de las desembocaduras de los ríos, mientras que en la época lluviosa suben a las lagunas con Igapó y Varzea. Existe mayor diversidad de comportamientos en lagunas con Igapó y Varzea, mientras que los delfines usan las secciones de río de poca profundidad y playas solamente como pasos migratorios. A pesar de que los Botos se consideran animales solitarios, observaciones en la Reserva Cuyabeno confirman un gran porcentaje de grupos de dos a ocho animales. Cuando hay crías, generalmente el tamaño del grupo es de tres a cuatro animales. El ámbito hogareño de los Botos en la Reserva Cuyabeno, según los estudios de foto identificación, se extiende a través de varios ríos entre el río Lagartococha y el río Cuyabeno con una extensión de más de 200 km, sin embargo, la mayoría de los delfines se mantuvo en un rango de 50km en sobre posición con otros grupos o delfines solitarios

Demographic studies of the Amazon river dolphin (Inia geoffrensis) in the Cuyabeno Reserve, Ecuador

Denkinger J. Demographische Untersuchungen am Amazonasdelfin (Inia geoffrensis) im Cuyabeno-Reservat, in Ecuador. Bielefeld (Germany): Bielefeld University; 2001.Amazonasdelfine (Inia geoffrensis) sind im gesamten Amazonas- und Orinocobecken verbreitet. In Ecuador kommen sie in den Flusssystemen des Pastaza, Curaray, Napo und Aguarico vor. Bisher gibt es nur sehr wenig Informationen über die Populationsdynamik, die Habitatnutzung oder das Sozialsystem von Inia, auch fehlen standardisierte Methoden, um beispielsweise Populationsschätzungen aus verschiedenen Studiengebieten miteinander vergleichen zu können. Darüber hinaus sind Flussdelfine durch die Zerstörung ihrer Lebensräume in ihrem Verbreitungsgebiet und auch im Cuyabeno Reservat bedroht. Das Verbreitungsgebiet des Amazonasdelfins im Cuyabeno Reservat erstreckt sich über ca. 381 Flusskilometer entlang des Aguarico und seinen Zuflüssen. Für die Populationsschätzungen wurden zwei verschiedene Methoden angewandt, die Strip Transect Methode, unter Einbeziehung der Sichtungswahrscheinlichkeit und die Methode der Mehrfachsichtungen von photographisch identifizierten Tieren. Die Sichtungswahrscheinlichkeit (p) von Inia wird signifikant vom Wasserstand und von der Größenklasse der Tiere beeinflusst und ist unter Niedrigwasserbedingungen am größten (p = 0,67). Die Populationsdichte im Cuyabeno Reservat schwankt von 0,04 Inia/km Fluss bei Hochwasser bis zu 0,47 Inia/km Fluss bei Niedrigwasser. Die Populationsgröße betrug 79 Tiere in der Trockenzeit von 1996/1997 und 60 Tiere in der Trockenzeit von 1997/1998, die über die Strip Transect Methode berechnet wurde. Im Vergleich dazu wurden 61,2 Tiere in der Trockenzeit von 1997/1998 über die Marc Recapture Methode ermittelt, was zeigt, dass die Methode eine weitere Möglichkeit für Populationsschätzungen von Amazonasdelfinen darstellt. Bevorzugte Habitate des Amazonasdelfins sind Lagunen mit Igapós und Schilfbereiche bei höheren Wasserständen sowie die Mündungsbereiche von Schwarzwasserflüssen mit Weißwasserflüssen bei niedrigen Wasserständen. In diesen Habitaten wurde auch das reichste Verhaltensspektrum beobachtet. Innerhalb des Reservats konnten mit Hilfe von identifizierten Tieren kurzfristige Wanderungen von bis zu drei Tagen von weniger als 20 km und langfristige Wanderungen bis über 200 km nachgewiesen werden. Das Reservat scheint eine große Bedeutung für die Aufzucht von Kälbern zu haben, da 30 v.H. der beobachteten Tiere Kälber waren. Dies kann unter anderem ein Grund dür die soziale Organisation der Tiere sein, denn Gruppen waren häufiger zu beobachten als Einzeltiere. Die Qualität des Lebensraums im Cuyabeno Reservat ist stark abhängig von den angrenzenden Ölfeldern, die ihre Abwässer in die Zuflüsse des Reservats entlassen, was durch mehrere Wasseruntersuchungen nachgewiesen werden konnte. Auch der Verkehr von Kanus mit Außenbordmotoren hat einen negativen Einfluss auf die Delfine und äußert sich unter anderem in der Erhöhung der Atemfrequenz. Der Status von Inia geoffrensis im Cuyabeno Reservat ist daher unsicher. Seit 1994 konnte ein geringfügiger Rückgang der Population der Amazonasdelfine beobachtet werden und Nachforschungen über die Präsenz des sympatrisch lebenden Tucuxi (Sotalia fluviatilis) ergaben, dass diese Art seit 1990 aus dem Reservat weitgehend verschwunden ist. Weitere Monitoringarbeiten über die Populationsdichte und -größe sowie eine intensivere Erforschung des Sozialsystems des Amazonasdelfins sind empfehlenswert für den Schutz dieser Art