blond titi monkey (Callicebus barbarabrownae)
Mohamed bin Zayed Species project number 212526312
Blond titi monkey populationsâ€™ size in the Chapada Diamantina National Park, Brazil
This project aims to estimate the abundance of the Critically Endangered blond titi monkey in the only strictly protected area the species is known to occurs, the Chapada Diamantina National Park in Brazil.
The blond titi monkey inhabits forests in the Caatinga biome, Northeastern Brazil. Though Caatinga is commonly known as a dry, cactus-rich vast scrubland, it wasn't always like this. Caatinga means "white forest" in the indigenous Tupi language: the dry forests were the main vegetation in this region, heavily changed by human activities (63%). Only 7% of the Caatinga is covered by protected areas, and 94% of the region has moderate to high desertification risk by land use and climate change.
Discovered only 30 years ago, the blond titi has been considered highly threatened to extinction by IUCN and Brazilian Red Lists. Titi monkeys (subfamily Callicebinae) are difficult to visually detect because they are cryptic and shy, living in territorial, small groups (3 adults in average). However, titi monkeys emit loud calls for intergroup communication and respond vocally to playback calls, and that is how we shed light on blond titi distribution and abundance.
In a previous project financed by The Mohamed bin Zayed Species Conservation Fund, we used playback sampling to find the species is more widespread and abundant than previously known and confirmed its occurrence in a strictly protected area (Alonso et al., 2022). We also presented the species' first accurate estimate of a population size: 273 adult blond titis in a 221‐km2 area in Boa Vista do Tupim, Bahia state (Coelho et al., 2020). However, we had also bad news: the remaining forest cover is still decreasing (11% loss from 2005 to 2016), and human occupation keeps growing extremely fast in the species' range (67% increase from 2005 to 2016; Alonso et al., 2022).
To estimate the number of individuals in protected areas is a key target in the blond titi Conservation Action Plan. Knowing the population size occupying different areas inside the Chapada Diamantina National Park is crucial for the park management and regional planning to promote connectivity of the remaining Caatinga forests. The results of this project are also intended to raise public awareness to the conservation of blond titi monkeys and its habitats, the "white forests" that we much need in their original place.
The fieldwork was finished in May 2023. Partial results and sampling effort can be seen in the Figures in the Project Documents below. We confirmed the occurrence of blond titis in three areas in Chapada Diamantina National Park (Figure 1): Lençóis, Marimbus, and Serra da Chapadinha. The species is probably extinct in the Baixão area and was not recorded in Vale do Pati, where it is not known by local people. Data analysis is ongoing to estimate blond titi distribution and abundance in the Chapada Diamantina National Park considering imperfect detection. The results will be published in a scientific article and in a report to the Chico Mendes Institute for Biodiversity Conservation (ICMBio, Ministry of Environment, Brazil).
References and Links
Alonso et al. (2022)
Coelho et al. (2020)
Chapada Diamantina National Park
Conservation Action Plan of Primates in Northeastern Brazil
- Fig11. Number of playback sampling occasions (days) in Study Area 5
- Fig8. Maximum number of blond titi groups recorded in playback points in Study Area 3
- Fig9. Number of playback sampling occasions (days) in Study Area 3
- Fig7. Number of playback sampling occasions (days) in Study Area 4
- Fig1. Study Areas in Chapada Diamantina National Park
- Fig2. Maximum number of blond titi groups recorded in playback points in Study Area 1
- Fig3. Maximum number of blond titi groups recorded in playback points in Study Area 2
- Fig4. Number of playback sampling occasions (days) in Study Area 1
- Fig5. Number of playback sampling occasions (days) in Study Area 2
Project 212526312 location - Brazil, South America