Dimas Gianuca

BirdLife International · Marine Program

Wading birds are key components of wetlands, transporting matter, energy, contaminants and associated organisms among limnetic, estuarine, terrestrial and coastal ecosystems. The role of cocoi herons (Ardea cocoi) in connecting these ecosystems was studied in the only known estuarine and limnetic colonies in coastal plains of southern Brazil. Food...

We document the expansion of the breeding distribution of the Little Blue Heron Egretta caerulea (Linnaeus, 1758) to 850 km beyond its previous southern limit in South America. In addition we present data on abundance, breeding biology and food of the species in the Patos Lagoon estuary, the area which the species recently colonized. The maximum ab...

Distribution records of poorly-known species are currently the most explored theme in the Brazilian seabird literature. If properly evaluated, this kind of information can improve our knowledge on distribution, migration and status of occurrence of these species. In this note we present new records for six species of poorly-known seabirds in the Br...

Large Procellariiformes (albatrosses and petrels) constitute a highly threatened group of birds, for which bycatch in fisheries is the most prevalent threat. At-sea intentional killing and post-capture, handling-related injuries, remain poorly understood menaces. Here, we report fishermen off southern Brazil trying to reduce bait depredation in pol...

Albatrosses are the most threatened group of seabirds and interaction with pelagic longline fisheries is one of the main factors of population declines. In this study, we present the largest time series about distribution and abundance of great albatrosses (genus Diomedea) associated with pelagic longline fisheries off south and southeast Brazil. A...

The Brazilian Albatrosses and Petrels Sample Bank-BAAP intend to promote quality and standardized storage of samples as well as the communication between educational institutions, museums, researchers interested in projects that benefit Procellariiformes conservation initiatives. BAAP may also help to enhance ornithological collections of Brazilian...

Many animal taxa exhibit sex-specific variation in ecological traits, such as foraging and distribution. These differences could result in sex-specific responses to change, but such demographic effects are poorly understood. Here, we test for sex-specific differences in the demography of northern (NGP, Macronectes halli) and southern (SGP, M. gigan...

Efforts to conserve biodiversity comprise a patchwork of international goals, national-level plans, and local interventions that, overall, are failing. We discuss the potential utility of applying the mitigation hierarchy, widely used during economic development activities, to all negative human impacts on biodiversity. Evaluating all biodiversity...

Bycatch of pelagic seabird species in longline fisheries is recognized as one of the most important and pervasive sources of mortality, contributing to an increased risk of their extinction. Uptake of mitigation measures to reduce seabird bycatch has not been widespread by the industry. Here, we present the results of 18 at-sea trials conducted bet...

Worldwide, in recent years capture fisheries targeting lower-trophic level forage fish and euphausiid crustaceans have been substantial (∼20 million metric tons [MT] annually). Landings of forage species are projected to increase in the future, and this harvest may affect marine ecosystems and predator-prey interactions by removal or redistribution...

This brief report was prepared in order to complement the information provided on the National Report and contains the some of the most important activities addressed to the conservation of ACAP species in Brazil. It is presented a summary about the implementation of NPOA-Seabirds/Brazil and the national rules for the mitigation measures, subject t...

We reevaluated the status of Willets (Tringa semipalmata) in southeastern South America on the basis of new observations and reviews of literature and on-line ornithological databases. Despite relatively few previous reports, our new data indicate that Willets are regularly present in low numbers in the region. Both Eastern (T. s. semipalmata) and...

Recently, electric fishing lights (EFL) have been adopted by the southern Brazilian pelagic longline fleet. Each EFL carries two AA batteries, and given its weight out of the water (~160 g) some fishermen argue this device is a replacement for the new line weighting regime of 60g within 2 m of the hook. A total of 66 repetitions during 11 sets were...

The interaction between foraging seabirds and baited hooks during setting operation is responsible by high level of albatrosses and petrels mortality, as well as reduces the fishing efficiency of the longline due to loss of baits. Experiments indicate that 60 g placed no more than 3 m from the hook is likely to achieve optimal these sink rates for...

Herein we present a checklist of the bat species recorded in the municipality of Rio Grande, coastal plain of Rio Grande do Sul state. Thirteen species of three families were recorded through field sampling, collection specimen analysis and bibliography compilation. Molossidae and Vespertilionidae, both with five recorded species, were the most rep...

Egretta caerulea, ranges from southern USA to northern Argentina, in South America inhabiting mostly estuaries and other coastal wetlands, usually breeding in mangroves. In the state of Rio Grande do Sul (RS), southern Brazil, only 13 records of this species were made, from 1983 to 2007. Here we have new records of E. caerulea from Rio Grande munic...

For nine days, the number of sally lightfoot crabs (Grapsus grapsus) in a 300 m² area within the brown booby (Sula leucogaster) colony and the activity of each crab were recorded in the morning (5:30-7:30 h), at midday (11:30-13:30 h), and in the afternoon (15:30-17:30 h). The average number of individuals was 80.2 ± 15.5 (59-111) in the morning, 3...

The aim of this note is to report the seasonal occurrence and breeding of Nyctanassa violacea in the Patos Lagoon estuary, southern Brazil, its new southernmost area of occurrence. The Pólvora Island, located in the Patos Lagoon estuary, was visited every 15 days from April/2000 to November/2006. Nevertheless, the N. violacea was found in the area...

Seasonal occurrence and breeding of the Yellow Crowned Night Heron Nyctanassa violacea in the Patos Lagoon estuary (RS, Brazil): the new southern geographic range of the species. The aim of this note is to report the seasonal occurrence and breeding of Nyctanassa violacea in the Patos Lagoon estuary, southern Brazil, its new southernmost area of oc...