Re-introduction of the Saker Falcon (Falco cherrug) in Bulgaria - preliminary results from the ongoing establishment phase by 2020

Abstract

Considered extinct as breeding species in the early 2000s, the Saker Falcon was recovered when the first active nest from the new history of the species in Bulgaria was discovered in 2018, formed of two birds that were re-introduced back in 2015. Currently, there is only one confirmed wild breeding pair in the country - the male from 2015 with a female changed in 2020, released again as a part of the programme, in 2016. This is a report on the preliminary results and analysis of the ongoing establishment phase of the re-introduction of the Saker Falcon (Falco cherrug) in Bulgaria - first ever performed for this species in the country and globally. The period studied is 2015-2020. Following the re-introduction activities started in 2011, the current phase is defined by standardised methodology and a unified approach. Analysed and presented are methods for captive breeding and hacking, the breeding performance of the falcons, the number of released individuals, data from the post-fledging dependence period and a model of population growth.

First Biochemical Comparison Between Saker Falcon Subspecies Falco cherrug cherrug and Falco cherrug milvipes

“…Eighty-two percent of all Saker Falcons that hatched in the WRBC during that period were released using the soft-release hacking method (Petrov et al 2021). The first nesting by released birds was discovered in 2018 (Dixon et al 2020, Lazarova et al 2021), and another nesting territory was found later. Since 2018, Saker Falcons have nested successfully in Bulgaria every year, and at least nine young fledged from wild nests in 2018–2022.…”

Genetic diversity and relatedness amongst captive saker falcons (Falco cherrug) in the Green Balkans’ Wildlife Rehabilitation and Breeding Centre in Bulgaria

“…The objective of the current stage of the species restoration project is to release 100 juvenile sakers over a five-year period (2020-2024). They are retained in the hack sites until independence through food provision in order to imprint on the area and return to it when they reach breeding age at around 3-years-old ( Dixon et al 2020 , Lazarova et al 2021 , Petrov et al 2021 , Petrov et al 2022 ).…”