Project Title:
Pellet Group Inventory (P.G.I.)
Issue/Problem Statement
Knowledge of the size of Nova Scotia's deer herd together
with condition, reproduction, age/sex ratios and mortality factors,
are used in assessing herd status and recommending hunting regulations.
As deer are very difficult to inventory directly, a method of indirectly
estimating numbers has been developed which is based on a count of deer
pellet piles deposited throughout the winter period.
The number of moose on mainland Nova Scotia are very
low and have continued to decline since 1981 when all hunting of moose
on the mainland was discontinued. Their low numbers and scattered distribution,
as well as infrequent periods of appropriate early winter weather required
to do proper aerial surveys, have resulted in an inability to monitor
their status. Consequently, a decision was made in year 2000 to transfer
staff effort every third year, from the deer P.G.I. program to conducting
a moose P.G.I. in areas of mainland Nova Scotia where it is logical
to strive to maintain a viable moose population. In the remaining areas
of the province, deer P.G.I. counts are maintained to provide some trend
information in these years.
Moose P.G.I.s were completed in spring 2000 and 2003,
with the intent of repeating the same sample plots in 2006, 2009,etc.,
for the purpose of monitoring trend in abundance and distribution. This
program is not intended to be used for estimating density or numbers
of moose but only to gain some insight into overall abundance (ie increasing,
stable, decreasing).
Objective
To estimate the size of Nova Scotia's over-wintering
deer herd in two of three years and to monitor relative abundance and
distribution of moose on mainland Nova Scotia in every 3rd year.
Methods
In spring, after the snow melts and prior to green-up,
DNR staff throughout the province survey some 460 (2 m wide, 1 km long)
randomly selected transects. The number of deer/moose pellet piles observed
are recorded. These numbers are used to calculate deer density and ultimately
estimate herd size. Every third year a number of these "deer" transects
on mainland Nova Scotia, are dropped and replaced with "moose" transects.
These moose transects have been located within areas known to be inhabited
by at least some number of moose. All remaining "deer" transects continue
to be completed in these years. Both deer and moose pellet piles are
counted on all lines.
Partners
Regional Services Staff
Project Dates and Duration
Depending on snow melt and green-up, field work completed
within April and May, annually.
Progress to Date
In Spring, 1999, overwinter herd size estimate was
71,085. This represents an increase of 6% as compared to Spring, 1998(67,069),
and a 66% increase over Spring 1995.
In Spring of 1986 herd size was estimated at an all
time high of 119,224. The 1986 herd size is felt to have exceeded range
capacity. Currently, herd size objective is 80,000 deer provincially,
as estimated by the P.G.I. survey.
Results of the Pellet Group Inventory (PGI) indicate
Nova Scotia's deer density peaked in 1986 at a provincial average of
2.74 deer/km2. Overwintering deer density estimates were lower each
year thereafter until the spring of 1995 when the average density of
deer in the province had dropped to just below one deer per square kilometre.
The 1996 PGI results indicated a slight increase in
provincial deer density and herd size continued to grow annually through
the spring of 1999. However, the overwintering deer density estimate
between 1999 and 2000 dropped by 11% and has continued to decline every
year since. The spring 2003 overwintering deer density estimate is 0.93
deer/km2.
Deer densities experienced in the mid 1980's are believed
to have exceeded the biological carrying capacity for deer in Nova Scotia.
The current overwintering deer density objective, as estimated by the
PGI, is 1.80 deer/km2, or roughly 80,000 deer province wide."
White-Tailed Deer Densities and Corresponding Population
Estimates Calculated From the Pellet Group Inventory, 1983 - 2003
| Year |
Average
Density (Deer/km2)
|
Population Estimate |
|
1983 |
1.84 |
82682 |
| 1984 |
1.96 |
86355 |
| 1985 |
2.43 |
107857 |
| 1986 |
2.74 |
124150 |
| 1987 |
2.49 |
112324 |
| 1988 |
2.00 |
91197 |
| 1989 |
1.76 |
78327 |
| 1990 |
1.70 |
75732 |
| 1991 |
1.26 |
55608 |
| 1992 |
1.28 |
57054 |
| 1993 |
1.16 |
53082 |
| 1994 |
1.00 |
45056 |
| 1995 |
0.94 |
42764 |
| 1996 |
1.02 |
46705 |
| 1997 |
1.29 |
58334 |
| 1998 |
1.49 |
67069 |
| 1999 |
1.71 |
71085 |
| 2000 |
1.52 |
68592 |
| 2001 |
1.21 |
56646 |
| 2002 |
1.15 |
51391 |
| 2003 |
0.93 |
43279 |
Reporting
Internal and available to public upon request.
Management Recommendations
- Complete the full Deer P.G.I. program survey 2 of 3 years on schedule
2001, 2002, ---, 2004, 2005, ---, 2007, etc.
- In areas of mainland Nova Scotia where it is feasible and logical
to maintain a viable population of moose, transfer same effort to
completion of designated moose transects, every third year. (i.e.
years 2000,2003,2006, etc.) During years of emphasis on moose,
complete remaining original (since 1983) deer transects to maintain
trend information and the ability to detect major deer population
changes, should that occur.
Final Report: Annual - June
Completion Dates: Ongoing annually |