Journal of Caribbean Ornithology

AbstractUrbanization has introduced novel materials for nesting birds, including anthropogenic debris that may be dangerous to adults and nestlings (e.g., entanglement or ingestion leading to injury or mortality). We present two observations of incorporation of man-made materials into passerine nests on St. Eustatius, Caribbean Netherlands. This is the first publication of such observations for St. Eustatius, and addresses a gap in literature that acknowledges the use of anthropogenic litter by landbirds in the wider Caribbean.

Abstract

Red-billed Tropicbirds have historically been considered rare visitors to the waters around the islands of Aruba, Curaçao, and Bonaire in the southern Caribbean. However, in recent years there has been an increase in documented records. We summarize all known Red-billed Tropicbird records for the region and review broader regional population and movement data to place this increase in records in context. We recommend continued careful documentation of Red-billed Tropicbird records on and around the islands of Aruba, Curaçao, and Bonaire and the implementation of a standardized monitoring pro-gram across the Caribbean range for the species to better understand the species' population status, trends, and breeding and at-sea distribution

Abstract

The island of Bonaire is a nesting location for at least four tern species: a subspecies of the Least Tern (Sternula antillarum
antillarum), the Common Tern (Sterna hirundo), the Royal Tern (Thalasseus maximus), and a subspecies of the Sandwich
Tern (Thalasseus sandvicensis eurygnathus). The island is also a significant nesting site for the Caribbean Least Tern (Sternula
antillarum) population. Our main objectives were to: a) measure and compare breeding success at five known nesting sites on
northern Bonaire, b) document and compare the impact of natural and introduced predators on each site, and c) give management
recommendations for increasing breeding success based on our results. Our nest counts from 2014 indicate a significant
decline in nest abundance compared to historical observations from the 1950s, matching previous studies and observations
from the last two decades. Among the five nesting sites in our study, terns at the two island sites had the largest number of
breeding pairs and achieved the greatest success, fledging a maximum of ~0.8 chicks per nest, compared to all other sites which
were connected to the shoreline. We recorded rats and cats as predators at the peninsula site and field observations suggested
that predation by Laughing Gulls (Leucophaeus atricilla) might also be occurring at two sites. Both natural and artificial islands
on hypersaline lagoons provide good nesting sites for terns on Bonaire as they are protected from mammalian predators. However,
recreational disturbance remains the single most serious and pervasive threat to the future of seabird nesting on Bonaire
and requires concerted action. We propose a list of management actions to increase the numbers of nesting terns throughout
the sites studied. Increasing protection from predators and human disturbance by making artificial nesting islands will provide
the potential for Bonaire, and its sister islands, to become major refuges for southern Caribbean metapopulations of these four
tern species.

Brown Boobies (Sula leucogaster) are known to roost on the northwestern coast of Bonaire, Caribbean Netherlands. A published account from the 1950s reported ~200 Brown Boobies roosting in this area, along with smaller numbers of two other seabird species, and described regular hunting raids by fishermen in which up to 100 birds were harvested. In 1969, this roosting area and its surroundings were designated as a 30-km² nature reserve, and hunting became illegal. Although seabird assemblages were not monitored subsequently, anecdotal reports suggest that the number of roosting seabirds had decreased dramatically to < 60 individuals. In 2008–2010, we conducted roost counts at seven sites in Washington-Slagbaai National Park in northwestern Bonaire. Most counts were substantially higher than the anecdotal reports, with a maximum of 240 Brown Boobies in July 2009. We saw no evidence of breeding and did not observe any banded birds. Other roosting birds—Masked Boobies ( Sula dactylatra) and Brown Noddies (Anous stolidus)—were also present in very small numbers.

Keywords

Bonaire, Brown Booby, Caribbean Netherlands, citizen science, roost, Sula leucogaster, Washington-Slagbaai National Park

Abstract:

Recent surveys for the Snowy Plover (Charadrius alexandrinus) on St. Martin reveal that the species is no longer a resident on the island. Following surveys from 1997–2005, when the species was annually detected and observed breeding, plovers were no longer observed on the island. Both human disturbance to nesting birds and predation by invasive species are potential causes of the extirpation.