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Table 1 Methods for estimating the timing of dispersal in juvenile raptors (emigration from the natal home range and independence from parental resources)

From: When do young birds disperse? Tests from studies of golden eagles in Scotland

Method

Description

Reference

1

First day beyond circular parental territory radius (half the mean nearest neighbour distance) – 2.9 km

[20, 21]

2

First day beyond the mean nearest neighbour distance – 5.8 km

[20, 21]

3

First day over 20 km from natal nest

[16, 20]

4

First day beyond circular parental territory radius (half the inter-nest distance) and not within that distance for 2 consecutive locations

[17, 20, 21]

5

First day beyond the mean inter-nest distance and not within that distance for 2 consecutive locations

[20, 21]

6

All locations over the mean distance to nest

[10]

7

First day beyond maximum ranging distance (9 km) and not within usual range (6 km) for the following 10 days

This study

8

Highest coefficient of variation over a 3 record period

[20, 21]

9

Highest coefficient of variation over a 5 record period

[20, 21]

10

Highest coefficient of variation over a 10 record

[20, 21]

11

Highest coefficient of variation over a 30 day period

[20, 21]

12

Maximum change in proportion of locations inside natal home range (-30 days: +30 days )

This study

  1. Methods 1-7 are distance threshold methods and 8-11 are coefficient of variation calculated around each day.