3 research outputs found
Breeding season of the Endangered White (Umbrella) Cockatoo, and possible competition for nest holes with Blythâs (Papuan) Hornbill in North Maluku, Indonesia
The White Cockatoo Cacatua alba is endemic to the North Molucca islands and is considered Endangered mostly due to unsustainable levels of trapping for the pet trade. Little is known about its breeding biology in the wild, except that it nests in tall trees during the early part of the year. We made brief observations of two active nests of White Cockatoos on Halmahera and another on Ternate in February and March 2014, and estimate the egg laying dates of two of these nests as mid-October and mid-November. Combined with other data, the breeding season appears to extend from October to May or June. All three nests were visited by Blyth’s Hornbills Rhyticeros plicatus, a species which occurs throughout North Maluku, as well as New Guinea. One nest was subsequently abandoned. In September and November 2014, we observed two active nest cavities of hornbills, one of which was inspected by a cockatoo, and the other, approached closely by cockatoos. Both hornbill nests were reported to have been used previously by White Cockatoos, suggesting that the two species may either share or compete for the same nest cavities. Sharing of cavities may be facilitated by partly non-overlapping breeding seasons, as Blyth’s Hornbill reportedly lays eggs from August to October in the region. However, as the nest cycle of both species is c.4 months, it is possible that early nesting pairs of one species may attempt to usurp nest cavities occupied by the other species. The potential for nest competition may be exacerbated on small islands where deforestation has reduced the number of nest cavities available for hole-nesting species
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A quantitative global review of species population monitoring
Abstract: Species monitoring, defined here as the repeated, systematic collection of data to detect longâterm changes in the populations of wild species, is a vital component of conservation practice and policy. We created a database of nearly 1200 schemes, ranging in start date from 1800 to 2018, to review spatial, temporal, taxonomic, and methodological patterns in global species monitoring. We identified monitoring schemes through standardized web searches, an online survey of stakeholders, inâdepth national searches in a sample of countries, and a review of global biodiversity databases. We estimated the total global number of monitoring schemes operating at 3300â15,000. Since 2000, there has been a sharp increase in the number of new schemes being initiated in lowerâ and middleâincome countries and in megadiverse countries, but a decrease in highâincome countries. The total number of monitoring schemes in a country and its per capita gross domestic product were strongly, positively correlated. Schemes that were active in 2018 had been running for an average of 21 years in highâincome countries, compared with 13 years in middleâincome countries and 10 years in lowâincome countries. In highâincome countries, over oneâhalf of monitoring schemes received government funding, but this was less than oneâquarter in lowâincome countries. Data collection was undertaken partly or wholly by volunteers in 37% of schemes, and such schemes covered significantly more sites and species than those undertaken by professionals alone. Birds were by far the most widely monitored taxonomic group, accounting for around half of all schemes, but this bias declined over time. Monitoring in most taxonomic groups remains sparse and uncoordinated, and most of the data generated are elusive and unlikely to feed into wider biodiversity conservation processes. These shortcomings could be addressed by, for example, creating an open global metaâdatabase of biodiversity monitoring schemes and enhancing capacity for species monitoring in countries with high biodiversity. Article impact statement: Species population monitoring for conservation purposes remains strongly biased toward a few vertebrate taxa in wealthier countries