Eurasian sparrowhawks (Accipiter nisus), common ravens (Corvus corax), tawny owls (Strix aluco) and northern goshawks (Accipter gentilis) monitored with BEAran Mobile Nest Monitoring (Modular) systems.
Monitored from horizontal distances of 10-35m from nests. Nests were located at heights between 21m and 37m (from ground level).
Mobile mast setup, monitoring and removal from territory took no more than 10 minutes per session.
Nest monitoring
Many species of birds are monitored globally, especially their reproduction, to track population trends. Some birds are considered excellent sentinel species and bioindicators of ecological health, meaning that aforementioned data is very useful to understand ecological health of the ecosystems they reside in (Derlink et al., 2018; Natsukawa & Sergio, 2022, BTO, 2018; Poirazidis, 2017; Van Hoogen et al., 2013; Van Turnhout et al., 2008). Including that for species richness and endemism patterns (Bibby et al., 1992; Brooks et al., 2001; Burgess et al., 2002). This research is used to guide conservation efforts.
More detailed info
I wrote an article about (mobile) nest monitoring. If you want to read more about this topic I advise to read this article. It can be accessed via the link behind the button below.
Translation to English is planned (September 2026).
Grey herons (Ardea cinerea), filmed with a BEAran NM⁴
Bearded vultures (Gypaetus barbatus), filmed with a BEAran NM⁴
High nesting species
Some of the most effective bioindicator species are high nesting birds (in trees and on cliffs) such as owls, ravens, vultures, herons and birds of prey (Assandri et al., 2023). Therefore a challenge to collect data, without disturbance.
Most reproduction data such as breeding performance, nest occupancy, and productivity (number of fledglings) can best or only be collected with visual and frequent nest monitoring. Mounting (semi-) permanent wildlife camera's up in all those trees and on cliffs is not an option due to the increased risks of ecological disturbance, significant cost of ownership and because, for several reasons, it is not an option to have camera's with batteries/solar panels and remote access at every nest. For a small country like the Netherlands alone you would already need to operate thousands of those to be able to monitor all the relevant nests.
A better option is to have a mobile nest monitoring solution which allows for fast, undisturbed nest monitoring utilized at well-timed data collection events. In this case roughly 1 system per 50-100 nests will be sufficient.
BEAran invented and designed one of the first mobile nest monitoring solutions in 2008.
BEAran Nest Monitoring Mast (Mobile)
In absence of a, commercially, readily available solution the BEAran systems have been one of the most used ones (I dare say until at least 2017 the most used), in Europe and the USA. The Nest Monitoring Masts (Mobile) designs (hardware, electronics and software) have been shared and are still being updated/upgraded and shared with numerous organizations since then, free of any costs and open-source. There are 2 categories of BEAran nest monitoring solutions.
The most popular, much less complicated and affordable system, suitable for 70% of all cases, is the NM³. This systems exist of an RGB camera, wireless transmitter, ground station and a telescopic mast which can reach heights up to 20m.
Common buzzards (Buteo buteo), filmed with a BEAran NM⁴
Long-eared owls (Asio otus), filmed with a BEAran NM⁴
An open-source design
If there is need to monitor the other 30% of cases, to monitor under more complicated conditions and in the most difficult situations, a system existing of several building blocks is offered, the NM⁴. The building blocks, or modules, can be combined to match those conditions and situations.
For this I developed a sophisticated ground station (CU²M) which can control several monitoring modules (RGB including zoom functionalities, near-infrared/’nightvision’, long-wave-infrared/’thermal imaging’, LIDAR and acoustic sensors). The lightweight mobile telescopic mast I developed to host those modules is by far the highest lightweight mobile carbon telescopic mast in the world, able to reach up to 44m.
Open-source design access
If you are interested in the open-source designs, the full Bill of Information (BOI) is available in this cloud. Contact me if you are a researcher or representative of a research, data collection or conservation organization to get access to the designs.