I investigated the numbers of Pinnipedia in King George Island with Daniel Torres N. from December 1983 to February 1984. We carried out the survey about the elephant seals during the moulting season, this was a new try, because previous investigations were made during the reproduction period.

Chart of the count area was shown in Figure 1. Observations were made by the naked eyes along the southern and the northern coasts from the east and the west of Marsh Base about 7km in length, 0.3km in width respectively. Numbers of the elephant seals, distinction of the sexes, and comparison of the densities of the southern and the northern banks were made, at the same time, we also used the helicopter to observe the animal distribution along the Island in order to verify if the samples were random.

Samples were divided into two groups: group A. including three points (I, II, III); group B, including two points (IV,V). We counted the numbers of two groups once a day, so that we could observe the appearance frequency of the male and the female, and the stability of the animal numbers. We also observed the daily changes of the animal numbers in group B.

The data, time, point, animal numbers, sex, behavior and weather conditions of the observations were recorded in every case. The feasible density was determined by analyzing all factors, then the total numbers of the elephant seals in King George Island was estimated.

The results were as follow:

1.  The average density of the southern and the northern banks Direct count results showed great differences in the densities of two banks, the mean of the northern bank was 111.29 individuals/km, and that of the southern bank was 5.14 individuals/km, so we could deduce that the elephant seals likes to be on the sunny bank, this result was also proved by the observations with the helicopter.

2.  Changes of the appearance frequency of the male and female:

a.  The male rate decreased, and the female rate increased with time during the moulting period (from December to January), so the male moulted earlier than the female.

b.  The male moulting peak was in December 27 or so, the female moulting peak was in several days after January 17. They moulted alternately, so the animals counted were only about half of all the numbers. The males and the females made the actual numbers of the elephant seals.

3.  Stability of the animals
From December 24, 1983 to January 22, 1984, we know that:

 Changes of the animal numbers at group A I ranged from 24 to 58. The mean was 41.45 (n=11, x=+6.76, p<0.05). December, 1983 was the time the animals reached the highest numbers. January 8-12 was the time of the lowest numbers this area might be the moulting place of both males and the females.

 At group A II, animal numbers ranged from 4 to 14, the mean was 8.60 (n=10, x=+2.09, p<0.05). The highest numbers was at the time January 6-7, the lowest ones was at the time January 8-11.

 At group A III, the numbers ranged from 9 to 17, the mean was 12.14(n=7, x=+2.33, p<0.05). The numbers of the elephant seals was relatively stable, and it increased gradually.

 At group B IV, the numbers ranged from 27 to 71, the mean was 53(n=7, x=+13.34, p<0.05). The numbers reached the highest after January 17, it was a typical moulting place of the female.

 At group B V, the numbers ranged from 27 to 59, the mean was 40.57(n=7, x=+10.25, p<0.05). The numbers reached the highest before January 8, it was a typical moulting place of the male.

 The average numbers of all animals observed at group A and B was 30.52(n=42, x=+16.68, p<0.05).

4.  Stability of the animals
The numbers counted in different time was changeable, but its ranges were not great, and there was no regularity. The numbers of two groups trended increasing and decreasing at the same time.

5.  Effects of weather, ground and moulting habits
The five points observed and counted might be grouped into three types:

 Point I, the ground was broad and smooth, no natural defense, it was influenced by the weather easily, therefore there were more animals during prevailing north wind, warm weather (0 C) and rising tide, for example, December 30 (58 individuals), January 6 (52 individuals) , January 11 (48 individuals) , January 19 (47 individuals) , and January 21 (51 individuals); on the contrary, there were fewer animals during prevailing south wind, cold weather (<o C), for example, December 27 (34 individuals) , January 7 (39 individuals) , January 9 (33 individuals) , January 12 (24 individuals), January 13 (37 individuals) . Variable coefficient of point I was 25.05%.

 Point II and Point III were less affected by the weather, under the protection of precipices and fine natural defense. Variable coefficients of point II and point III were 35.61%, 23.50% respectively.

 Point IV and point V were the moulting place of the males and the females separately. When the numbers of point IV increased with time, and that of point V decreased. Variable coefficients were 30.83%, 30.94% respectively.
According to the variable coefficients above, we knew that II, IV, and V counts were dispersed, and considered to be unstable.

6.  Estimate of the individual numbers
The density of the Northern bank in direct count was 114.29 individuals/km, and that of both banks was equal, the perimeter of the Island was 201 km, observing width was 0.3 km, so the counting area of each bank was 201 x 0.3/2 = 30.15 km. It was calculated that the numbers of the elephant seals of the Northern bank was 3445.84, and that of the Southern bank was 157.99, therefore there were 3604 elephant seals in King George Island, if we regarded the limit error that we observed and counted repeatedly from December 24, 1983 to January 22, 1984 as counting error (n=42, error=42 x 6.68 = 280.56), then the numbers of the elephant seals in the Island could be calculated, it ranged from 3323 to 3885, but we did this work during the moulting period, the numbers observed was only the half of the actual ones, which was from 6646 to 7700 in King George Island, this result was similar to that of Aguayo in 1970 (Aguayo estimated the numbers of the elephant seals in King George Island was from 6940 to 7515).