Penguin Report May 2005

Population Size

It looks like the size of the colony this year is around 1025 individuals. They have had a very good season and apart from the storm in December where we lost a few, they are thriving.

Breeding

In May the colony was treated to large shoals of anchovy just off shore, which gave them a very good start to the penguin year (May to April), and they immediately started turning their thoughts to the breeding season. The first two sets of eggs were laid in early June. By July we had 4 new sets of eggs and 11 pairs of penguins. The penguins chicks continued to come until January and the last chick fledged at the end of March.

Moult

All of the penguins started to moult during the last week of February, which is quite unusual as they normally start around late December and finish in April. This means that we currently have lots of beautiful penguins in their new feathers. They all look very healthy and some are beginning to pair up (May 2006).

Characters in the Colony

Our well-known penguins at the foot of the board walk steps were one of the first layers. Two chicks hatched and they successfully reared one chick. They laid a second set of eggs later in the year. The male of this pair has only one leg but he climbs the rocks with no problems and challenges all and sundry when the burrow is approached. He has never let us catch his mate and it’s often hard to catch his chicks. They have bred every year since 2001. Being on full view to the public has not deterred them in the slightest.

The pair of penguins on the seaward side of the bend of the breakwater was washed out of their burrow in the February storms and their burrow was filled with small stones.

We removed most of the stones and they built a new nest and reared two healthy chicks early in the season. They reared another chick before Christmas.

19108506 gets caught regularly she was a big healthy 1500 grams, in July and is with her usual partner 621552D, although she did have a brief fling with 635F88A in May.

6353987 and his partner 670A00B are wanderers. They have been caught together three times this year in three different places on the breakwater

We were happy to see 71985 in November. She was born on the breakwater in 1993. Last moulting season we thought she would not survive, as her feathers were very brown. But she is alive and well and living in the same burrow. One 18-year-old penguin was found on the beach in June and died overnight. He had been evading us for years only having been caught 6 times.

In September we caught 63574 first seen in 1991. We had not seen him since 2002. He was first caught as an adult so is probably 16 or 17 years old. He has successfully reared two sets of chicks that we know of and has always lived in the same spot next to the yacht tower.

Our oldest surviving penguin 41711, born in 1989 is still defending his territory, but his partner was tragically hit with a rock. He did manage to feed one of the chicks and we think it fledged.

The other older pair 51240 and his mate 82228 are still in their prime real estate on the top of the bend in a three-room apartment overlooking the city, with sea views to the rear. It is shaded from the afternoon sun by a large salt bush.

The penguin 108502 was caught 9 times. He was first caught in January 2001, has always lived around B.3. and usually weighs around 1100 grams. He did manage to get to just on 2000 grams premoult this year. His partner is 103933. She was born in October 2000 at Q.6 and is a very small penguin. We have never recorded her with eggs or chicks.

Penguin Recordings

Teams in the 2005/06 season contained many more experienced observers than in previous seasons. These observers also subjectively felt they were now better organized within teams.

Penguins recorded by season:

The penguin season runs from May to April each year.

Season	Caught Adults	Caught Chicks	Caught Total	Seen but not caught Adults	Seen but not caught Chicks	Seen but not caught Total
2005/06	880	59	939	1846	234	2080
2004/05	684	39	723	1788	244	2032
2003/04	426	38	464	1123	178	1301

Number of captures by season and per visit:

Season	Number visits	Caught Adults	Average Adults caught per visit	Caught Chicks	Average Chicks caught per visit	Caught Total	Average catches per visit
2005/06	23	880	38.27	59	2.57	939	40.82
2004/05	24	684	28.50	39	1.62	723	30.13
2003/04	17	426	25.06	38	2.24	464	27.29

Number of penguins seen but not caught:

Season	Number Visits	Seen not caught Adults	Average Adults seen not caught per visit	Seen not caught Chicks	Average Chicks seen not caught per visit	Seen not caught Total	Average seen not caught per visit
2005/06	23	1846	80.26	234	10.17	2080	90.43
2004/05	24	1788	74.50	244	10.17	2032	84.67
2003/04	17	1123	66.06	178	10.47	1301	76.53

Adult penguins caught as percentage of number seen and caught:

Season	Adults
2005/06	32.9%
2004/05	27.7%
2003/04	27.5%

Frequency of recapture within a season:

Number of times caught	1	2	3	4	5	6	7	8	9	Total of penguin catches	Number caught irrespective of recapture
2005/6	346	107	56	28	13	2	2		1	939	555
2004/5	301	101	38	20	4	1				723	465
2003/4	225	66	17	6	4	2				464	320

Number of penguins microchipped:

Year	Male	Female	Not sure of sex	Chicks	Total
2005/6	62	96	14	52	224
2004/5	61	93	12	26	192
2003/4	62	111	12	32	217

Breeding Sites and population estimates

Season	No Breeding Sites	Population Estimate
1998/99	71	329
1999/00	67	310
2000/01	95	441
2001/02	93	432
2002/03	92	427
2003/04	112	520
2004/05	146	677
2005/06	221	1025

Weight

How much does a penguin weigh? Their weight varies over the year but they are always much heavier just before moutling. We also get peaks in the weights when there are large shoals of anchovy just off shore. Each year in July there is a small peak in weight but August seems to be a leaner month. See following graphs of average weights over 3 seasons.

Graphs of average weights (top female, bottom male) measured over seasons 2003/4, 2004/5 and 2005/6.

Breakwater Management

We have had problems with the fishermen who continually cut the fence and gate and leave their rubbish and fishing line on the breakwater. Hopefully we will have a new fence built in the next few months.

A sign advising people that they are entering the St Kilda Breakwater Wildlife reserve and that dogs are not permitted, will be part of the bollard to be installed at the junction of the pier and breakwater

Volunteers

We now have three search teams due to the large number of penguins but this means we must find at least 15 experienced volunteers each time, which is not always easy. It is important that information is recorded accurately for each penguin (ie location and stage of chick or moult).

Many thanks to the penguin teams for their dedication often in very difficult conditions.

Penguin Report May 2005 – April 2006

Number of captures by season and per visit:

Number of penguins seen but not caught:

Number of penguins microchipped:

Breeding Sites and population estimates