Urban parakeet by Dr Matt Geary

Urban parakeet
Feeds in small parks and gardens
Missing from forests

By Matt Geary

As with many islands around the world, the island of Hispaniola in the Caribbean is home to a number of bird species found only there. Hispaniola is divided between two countries, Haiti and the Dominican Republic. Both countries have experienced severe environmental change since European colonisation, including considerable forest loss and agricultural expansion. Hispaniolan parakeet (Psittacara chloropterus) is hard to find across the Dominican Republic but a considerable population lives in the capital city, Santo Domingo. Our work explores how these vulnerable island endemics use the urban environment.

In 2019, our research team spent three months walking through parts of the city where parakeets are found, counting birds as well as measuring the natural environment around them. They covered 60 1 km2 squares of Santo Domingo, visiting each square three times. As well as looking for parakeets, they recorded sightings of another endemic, Hispaniolan woodpecker, a species which makes cavities in trees where parakeets are potentially able to nest. The team were also on the lookout for parakeet nest sites in trees and buildings.

Hispaniolan parakeet (Psittacara chloropterus). Image credit: Martingloor.

The population in the city is certainly large. We counted around 1500 birds at a communal roost site in the city centre and saw lots of birds on our surveys. We found that parakeet distribution within the city was related to the number of different tree species within the square and saw more parakeet groups where there were more small greenspace patches. This suggests Hispaniolan parakeets are using street level green spaces like small parks and gardens for foraging rather than relying on large areas of vegetation. We only found three locations where parakeets were nesting, all of which were previously know – one palm tree and two communal roosts in buildings.

This species certainly needs some support across the island of Hispaniola and we hope that by improving our knowledge about this population, which may be the largest remaining, we can help to improve the outlook for the species as a whole. Our work continues on this species and other Hispaniolan endemics. @AndreaThomen is putting the miles in with survey work across the island for her PhD research so we hope to have much more to report in the near future.

Further reading: Geary, M., Brailsford, C.J., Hough, L.I., Baker, F., Guerrero, S., Leon, Y.M., Collar, N.J. and Marsden, S.J., 2021. Street-level green spaces support a key urban population of the threatened Hispaniolan parakeet Psittacara chloropterus. Urban Ecosystems, pp.1-8. https://link.springer.com/article/10.1007/s11252-021-01119-1

Dr Matt Geary (https://mattgeary.github.io/) is a Conservation Ecologist working in the Conservation Biology Research Group at the University of Chester. Twitter: @MattGeary

Small and spherical

Small and spherical,

the eggs of forest blue tits.

Urban differences.

 

Populations of many species live in different environments that provide varied resources and have differing selection pressures. Research by Bańbura et al (2018) investigated the eggs of blue tits living in a forest environment compared to a nearby urban park.

The researchers found that urban-dwelling blue tits produced eggs that were on average 5% larger than their forest-dwelling counterparts, and the urban eggs were less spherical as well. These differences are potentially the result of blue tit diets in each environment – the forest is caterpillar-rich but calcium-poor whilst the urban park is the opposite, with 5-6 times the density of snails which have calcium-rich shells. The smaller, rounder forest egg shape requires less calcium compared to the less spherical urban egg shape.

Original research: http://dx.doi.org/10.1186/s12983-018-0279-4

Wild, rural, urban

Mammal density

wild, rural, urban – the same.

Rocking the suburbs.

 

Urban development encroaches on natural spaces, reducing and altering animal habitats. A consequence of this is that many species have evolved to live around humans, although developed areas are thought to have low species diversity and abundance.

Yet research by Parsons et al (2018) in coordination with citizen scientist volunteers suggests this might not be the case. Using camera traps placed in areas of varying development (from wild to urban) and scale (from forests to yards) the researchers found that mammals were found in similar or higher levels of abundancy and species richness in developed areas compared to wild areas. The research highlights the need to conserve wild areas and preserve green spaces within cities.

The keen eyed may spot that the final line of this sciku is a reference to Ben Folds’ first solo album ‘Rockin’ the Suburbs’, released in 2001.

Original research: https://doi.org/10.7554/elife.38012.001