This discussion was first published as part of the 2016 Red List update. At the time a decision regarding its status was pended, but to enable potential reassessment of this species as part of the 2018 Red List update this post remains open and the date of posting has been updated.
BirdLife species factsheet for Helmet Vanga: http://www.birdlife.org/datazone/species/factsheet/22708058
This species is known from the lowland rainforest of north-eastern Madagascar, where it is uncommon and patchily distributed. It is currently classed as Vulnerable because of suspected continuing declines in its small range due to the conversion of its forest habitat.
Recent modelling analyses investigating the possible impact of climate change have suggested that this species’s ecological niche could nearly disappear over the 50 year period between 2000 and 2050 (Andriamasimanana and Cameron 2013). Assuming a linear decrease, this would equate to a reduction in its ecological niche of c.63% over the next 3 generations for this species (21 years). Thus it would qualify to be uplisted to Endangered under criterion A3bc.
We welcome any comments on this proposed uplisting.
Andriamasimanana, R. H.; Cameron, A. 2013. Predicting the impacts of climate change on the distribution of threatened forest-restricted birds in Madagascar. Ecol. & Evol. 3: 763-769.