A Rocha Kenya bird ringing data from Arabuko-Sokoke Forest and Gede Ruins Forest, Kenya, 2019

Study Extent

Mist netting was carried out between 1998 and 2015 at a range of different locations in Arabuko-Sokoke Forest and Gede Ruins either to study a particular species (e.g. Spotted Ground Thrush), as part of regular, constant effort monitoring of forest avian populations or for training and demonstration purposes. In most cases, nets were opened before dawn and patrolled for a minimum of four hours from dawn and the same protocol repeated for a second morning. Only in rare cases were nets run for just a single morning – or for more than two days. Again, in most cases, net sites were located in forest between 10 and 80 m from an existing trail and were angled according to what was taken to be the most likely angle to maximise capture.

Sampling

The main data collection method was mist netting. A handful of birds, mainly nightjars and raptors, were caught by hand through dazzling the bird with a torch at night or using a Bal Chatri trap for raptors (Berger & Mueller, 1959). Mist nets were erected the day before the capture of birds was carried out and closed overnight. They were unfurled before dawn and left undisturbed from before the time the first bird started calling before the first net round was carried out c.40 mins after opening. Birds caught were ringed with a ring from the Ringing Scheme of East Africa and biometrics taken: maximum chord wing length, bill + skull, tarsus (taken from back of folded knee to folded foot), mass (measured to nearest 0.1 g). Moult of primaries and secondaries were recorded on most birds and body moult on a selection. The age of each bird was determined from past experience with the same or similar species and where uncertain recorded as ‘Unknown’. In most cases, the net was recorded in which each bird was caught and the time of the net round noted. The data were formatted according to the Darwin Core Standards by A Rocha Kenya before publishing through the IPT at the National Museums of Kenya, Nairobi.

Quality Control

Careful assessment of the skills of ringers involved in the data collection was carried out. Data collected and entered to the A Rocha Kenya ringing database were checked for errors by CHWJ who also geolocated the ringing sites as he was involved in the majority of ringing events.

Method steps

1. The main data collection method was mist netting. A handful of birds, mainly nightjars and raptors, were caught by hand through dazzling the bird with a torch at night or using a Bal Chatri trap for raptors (Berger & Mueller, 1959). Mist nets were erected the day before the capture of birds was carried out and closed overnight. They were unfurled before dawn and left undisturbed from before the time the first bird started calling before the first net round was carried out c.40 mins after opening. The birds caught were then ringed with rings unique to each bird and their biometrics entered in the A Rocha Kenya’s ringing database. From the ringing database, data was then entered into a spreadsheet according to Darwin Core format for sampling-event.

All birds caught and ringed were identified to species level.

1. Cercotrichas quadrivirgata (Reichenow, 1879)
   common name: Bearded Scrub-robin rank: species

Birds caught and ringed in Arabuko-Sokoke Forest and Gede Ruins. Latitude of 3° 20’ S, Longitude 39° 50’ E