Vocalization of Hylodes meridionalis (Mertens 1927) (Anura,Hylodidae) in Rio Grande do Sul,Brazil, with comments on nocturnal calling in the family Hylodidae

We describe the advertisement and territorial calls of Hylodes meridionalis for the first time and provide observations on nocturnal calling activity for this species. The advertisement call has 36–82 harmonic notes, with duration of 2.71–5.69 s and dominant frequency on the third harmonic. Advertisement calls are separated by large intervals varying from 18.7 to 44.7 s. The territorial call has 1–3 notes, with duration of 0.039–0.567 seconds, and dominant frequency also on the third harmonic. Territorial calls are emitted at a much higher repetition rate than the advertisement call, with intervals of 1.1–1.6 s between each call. Frogs of the genus Hylodes are known to call mainly during the day, but for H. meridionalis nocturnal calling was observed on various occasions, and could occur regularly until two hours after sunset, or sporadically along the night.

Descrevemos os cantos de anúncio e territorial de Hylodes meridionalis pela primeira vez e fornecemos observações sobre a atividade noturna de vocalização para esta espécie. O canto de anúncio tem 36–82 notas harmônicas, com duração de 2,71–5,69 segundos e frequência dominante no terceiro harmônico. Há grandes intervalos entre os cantos de anúncio, de 18,7–44,7 segundos. O canto territorial tem 1–3 notas, com duração de 0,039–0,567 segundos, e frequência dominante também no terceiro harmônico. Cantos territoriais são emitidos a uma taxa de repetição muito mais elevado do que o canto de anúncio, com intervalos de 1,1–1,6 segundos entre cada canto. As espécies do gênero Hylodes são conhecidas por vocalizar principalmente durante o dia, mas machos de H. meridionalis foram observados em atividade de vocalização noturna em várias ocasiões, sendo que podem vocalizar regularmente até duas horas após o pôr do sol, ou esporadicamente ao longo da noite.     

Modelling the effect of fishing on southern Buller's albatross using a 60-year dataset

Abstract

Many albatross populations are declining and a major cause is believed to be incidental mortality from fishing. We investigated the effect of fishing on southern Buller's albatross Thalassarche bulleri bulleri, using a new approach to seabird population modelling that allows estimation of demographic parameters from multiple data types. Three types of data were used: a 60-year set of mark–recapture observations, four censuses of the breeding population, and estimates of fishing effort and bycatch. The fisheries risk to the viability of this population over the last 60 years appears to have been small, since the adult population is estimated to have increased about five-fold over that time. There is some cause for concern in recent changes (population growth has slowed, and perhaps reversed, and adult survival rates are falling). The most common age at first breeding was 12 years, and about 80% of adults breed each year. Annual survival was estimated to be 0.91 for juveniles, and varied between this value and 1 for adults. Though this population is not in immediate danger from fishing, there is a need for continued monitoring to see whether the recent fall in survival rates persists and causes a decline in abundance. Our analysis showed that when, as is common, mark–recapture data do not provide good estimates of all demographic rates, the assessment of seabird population trends can be improved by the use of other types of data, particularly abundance.     

Notes on New Zealand mammals 8. Predation on nesting southern royal albatrosses Diomedea epomophora by a New Zealand sea lion Phocarctos hookeri

Abstract

This note documents unusual predation of southern royal albatrosses Diomedea epomophora on land by an individual New Zealand sea lion Phocarctos hookeri. During a survey of albatross nests on Campbell Island in the New Zealand sub‐antarctic in January 2005, 128 corpses of adult albatrosses were found at or near nests within a 230 ha area. Flattened vegetation and flipper prints near the nests suggested sea lion predation, and subsequently a male sea lion was found near a line of freshly killed birds. The predation rate was estimated to be at least seven birds per day over a number of weeks; similar skeletal remains from the previous year were observed in a neighbouring area. The impact of one threatened species on another can be a dilemma for conservation managers. In this case, apparently only one male sea lion was involved and, because of the ongoing impact to the albatross population, permission was obtained to cull that individual on 17 January 2005. No further incidents were observed over the following three seasons (2006–08).     

Exploring the Afromontane centre of endemism: Kniphofia Moench (Asphodelaceae) as a floristic indicator

Aim The genus Kniphofia contains 71 species with an African–Malagasy distribution, including one species from Yemen. The genus has a general Afromontane distribution. Here we explore whether Kniphofia is a floristic indicator of the Afromontane centre of endemism and diversity. The South Africa Centre of diversity and endemism was explored in greater detail to understand biogeographical patterns. Location Africa, Afromontane Region, southern Africa, Madagascar and Yemen. Methods Diversity and endemism for the genus were examined at the continental scale using a chorological approach. Biogeographical patterns and endemism in the South Africa Centre were examined in greater detail using chorology, phenetics, parsimony analysis of endemicity (PAE) and mapping of range‐restricted taxa. Results Six centres of diversity were recovered, five of which are also centres of endemism. Eight subcentres of diversity are proposed, of which only two are considered subcentres of endemism. The South Africa Centre is the most species‐rich region and the largest centre of endemism for Kniphofia. The phenetic analysis of the South Africa Centre at the full degree square scale recovered three biogeographical areas that correspond with the subcentres obtained from the chorological analysis. The PAE (at the full degree square scale) and the mapping of range‐restricted taxa recovered two and six areas of endemism (AOEs), respectively. These latter two approaches produced results of limited value, possibly as a result of inadequate collecting of Kniphofia species. Only two AOEs were identified by PAE and these are embedded within two of the six AOEs recovered by the mapping of range‐restricted taxa. All the above AOEs are within the three subcentres found by chorological and phenetic analysis (at the full degree square scale) for the South Africa Centre. Main conclusions The centres for Kniphofia broadly correspond to the Afromontane regional mountain systems, but with some notable differences. We regard Kniphofia as a floristic indicator of the Afromontane Region sensu lato. In southern Africa, the phenetic approach at the full‐degree scale retrieved areas that correlate well with those obtained by the chorological approach.     

Germination responses of Reaumuria vermiculata to salinity and temperature

Reaumuria vermiculata is a xerohalophytic perennial dwarf shrub distributed in many gypseous and saline areas in southern Tunisia. A laboratory experiment was carried out to assess the effects of temperature and salinity on germination. The germination responses of the seeds in darkness were determined under a range of salinity and temperature regimes. Temperatures between 10°C and 30°C seem to be favourable for the germination of this species. Germination was inhibited by either an increase or a decrease in temperature from the optimal temperature (15°C). Highest germination percentages were obtained under non-saline conditions and increases in salinity inhibited seed germination. Salt stress decreased both the germination percentage and the germination speed (increase of the mean time to germinate). Seed germination decreased with an increase in NaCl concentrations at all temperatures. An interaction between salinity and temperature yielded no germination at salinity of 300 mM, whereas some seeds germinated under the optimal temperature.     

Site fidelity and association patterns of a rare species: Pygmy killer whales (Feresa attenuata) in the main Hawaiian Islands

Most of what we know about cetacean biology and ecology comes from studies of relatively common species. Despite their distribution throughout the tropics and sub-tropics, pygmy killer whales ( Feresa attenuata ) are rare throughout their range and are one of the most poorly-known species of odontocetes. During a 22-yr study of short-finned pilot whales ( Globicephala macrorhynchus ) off the island of Hawai'i, we opportunistically photo-identified pygmy killer whales whenever encountered. As part of a directed multi-species study throughout the main Hawaiian Islands from 2000 through 2007, we also photo-identified individuals and obtained information on habitat use and behavior. This species was extremely uncommon (representing only 1.2% of odontocete sightings in directed efforts). Given the low encounter rates, assessing trends of this population cannot be feasibly done with line-transect surveys. Despite their rarity, 80% of the distinctive individuals within groups documented off the island of Hawai'i were seen on multiple occasions, individuals were resighted over periods of up to 21 yr, and there was evidence of year-round use of the area. Association analyses indicate stable long-term associations in mixed-sex groups. High resighting rates indicate a small population of island-associated individuals that may be at risk from anthropogenic impacts.     

Complex effects of climate change: population fluctuations in a tropical rodent are associated with the southern oscillation index and regional fire extent,but not directly with local rainfall

We report on the population response of a species of rodent, Necromys lasiurus, to southern oscillation index (SOI) and extent of regional fire in an Amazonian savanna. Information on temporal variation in local abundance of N. lasiurus in a 4.0 ha savanna plot was obtained from 1985 to 1989, from 1997 to 1998 and 2000–2006, giving data on 14 of the 22 years. Throughout this period, rodent density declined by 90%. Densities were positively associated with SOI and the extent of fire in the region. Rainfall was related to SOI and negatively influenced the extent of fire. However, the amount of rain had no measurable direct effect on rat densities. Thus, small changes in temperature, and consequently fire probability and intensity, may have drastic consequences on the biota of Amazonian savannas, especially in El Niño periods.     

Prey of White-throated Hawks (Buteo albigula) in the southern temperate forest of Argentina

ABSTRACT.   We examined the diet of White-throated Hawks ( Buteo albigula ) during the incubation and nestling periods in the southern temperate forest of Argentina. Pellets ( N = 74) and prey remains ( N = 59) were collected at 10 nests from 1998 to 2003, and preys delivered to two nests were monitored during the 2001–2002 breeding seasons. White-throated Hawks fed on small mammals, birds, lizards, and insects. The three methods of identifying prey (pellets, prey remains, and direct observation) produced different results. All types of prey except large birds were detected in pellets, and arthropods may have been over-represented in pellets due to secondary consumption. No remains of either arthropods or reptiles were identified among prey remains collected at nest sites and, during nest observations, we were unable to identify many of the prey items delivered by adults. Our results indicate that accurate determination of the diet of White-throated Hawks requires more than one method of identifying prey.