Fate of released pheasants

Key findings

• 25% of released pheasants died before the shooting season began.
• Most predation was due to foxes.
• 37.5% of released pheasants were shot on (or off) the estate.
• 16% of released pheasants survived until after the shooting season.

This study was designed to document the mortality of released pheasants in relation to the density or scale of the release and the quality of the local habitat and its management. This is part of a larger on-going study looking at dispersal, which will be reported next year. We undertook fieldwork at six large releasing estates in southern England over the last three years.

The study used six open-topped release pen sites, three with poor and three with good local habitat quality. We varied the size of the release each year, but we kept other management components, in particular predator control and feeding, constant from year to year.

We fitted a sample of 25 to 30 birds in each release pen with radio-tags two to three weeks after release into the pens. Then, using a radio receiver, we located them several times each week over the pre-shooting period and during the shooting season and recorded their fate.

The study sites represent estates releasing 8,000 to 28,000 birds over 700 to 2,000 hectares, with one or usually more full-time professional gamekeepers managing the pheasants. The study pens are in the range 0.2 hectares to 1.4 hectares, normally containing between 400 and 1,200 pheasants, but up to 2,000 as part of our study of density.

The overall survival of 325 radio-tagged, hand-reared pheasants is shown in Figure 1. Steady losses, due mainly to predation, occurred between the time of release in July/August and the start of shooting in late October or early November, with 75% of the radio-tagged birds surviving until shooting began on the estates. Before shooting started, the rate of mortality dropped but, unsurprisingly, the number of birds dying then accelerates during the shooting season, so that by the end of the season, around 15% of birds remained alive. Although the pattern of survival varied at each of the six study sites, the data provide a useful insight into the overall survival of hand-reared pheasants released in the UK. Differences in mortality between estates were not related to the density or scale of the releases.

Figure 1: Survival of 325 radio-tagged pheasants after release into open-topped pens

The actual fate of the pheasants (see Table 1) shows that, overall, shooting was the cause of death for 37.5% of the radio-tagged pheasants, with predation being the next biggest reason for loss (although one estate lost 75% of the stock in one release pen in one year to predators). Of the tagged birds, 23% were predated or scavenged - the great majority by foxes - before shooting began (a figure comparable to birds in the wild). A further 13% were predated or scavenged during the shooting season (some of which may have been shot but not picked up). Of the 486 radio-tagged birds, we think three were killed by raptors. Disease and accidental deaths, such as collisions, also resulted in death of around 10% of the birds studied.

Table 1: Fate of released pheasants

Early pen death: disease, accidents, etc.
Predated: mostly by foxes
Scavenged: died of other causes before being eaten by foxes
Other: mostly road kills

The study followed, on average, 27 radio-tagged pheasants from six release pens on six estates in each of three years.

In addition to documenting the general survival trends and causes of mortality in released pheasant populations, this study has also generated large quantities of data concerning the movements and dispersal of pheasants. Once we have analysed the data fully in 2004, we hope to have a better understanding of the role played by density or scale of the release, and the quality of local habitat on both the survival and dispersal of released pheasants.