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Monday, February 29, 2016

It's safe to age in Estonia - the oldest Arctic Tern 28!


Matsalu Ringing Centre announced the eldest recaptured Arctic Tern in their history. It was captured in Denmark at the age of 28 years and 1 month. This bird was ringed on June 21, 1987 in Saaremaa by Mati Martinson, recaptured and released on July 30, 2015 in North Jutland, Denmark. Previous record was held by a 26 years old bird from 2005, when it was found dead in an Eagle Owl's nest.
The eldest Arctic Tern in Europe was 30 when captured. World's eldest Arctic Tern was captured in North-America at the age of 34 years.

Arctic Tern / Source: maaleht.delfi.ee



Marta - world's eldest Common Gull

Common Gull (Larus canus) population studies in Estonia

text by Kalev Rattiste & Peeter Vissak

Flash back! Year 1981 – assassination attempts to Pope John Paul II and president Ronald Reagan, Prince Charles marries Diana Spencer and Marta - one of many Common Gull chicks is hatching in Matsalu National Park, West-Estonia. Now we know her well, as she is the eldest known specimen of the species in the World.

Long-term individual based research of common gulls were initiated in 1962 by Estonian ornithologist Sven Onno. This species was selected as a model one due to its suitability for population studies (high birth rate and breeding site fidelity, insensitivity to human activities in the colony, both partners easily identifiable and catchable etc). The main aim was to study different aspects of  evolutionary ecology, including demography (e.g. reproduc­tive success, age at first breeding, survival, pair bond stability, longevity, birth site fidelity, wintering site fidelity), quantitative genetics and ecophysiology. 

Study area consists of three offshore islets in Matsalu National Park. Main studies are conducted on Kakrarahu islet (3.5 ha; 58º46’ N 23º26’ E). Nowadays, more than 750 pairs are breeding in this colony (all nests are marked and numbered). All breeders are ringed both with metal (Estonia Matsalu ringing scheme) and plastic ring (white rings with four alphanumerics, starting always with letter P, e.g. P3H9, P27K). Every year at least 95 per cent of breeders are identified and all hatched chicks are ringed in their first day of life. By everyday inspections laying time and weight of eggs, as well as hatching time of chicks are recorded.

In non-breeding period, many bird watchers observe these common gulls in their post-breeding wandering range, migration routes or wintering grounds. For example, in 2013-2015 there were 308 such notifications. Most often our common gulls are met in the Netherlands (42% of observations), Germany (26%), Denmark (18%) and Poland (4%), but also in Belgium, UK, Latvia, France, Sweden, Russia, Lituania, Czech Republic and Hungary, If you see an Estonian common gull, please inform Estonian Ringing Centre (matsalu@envir.ee) or directly our study group (kalev.rattiste@gmail.com).

Marta and Oskar in 2012 / Source: laanlane.ee

As a rule, only ten per cent of offspring reach sexual maturity and start to breed. On average common gulls breed for five-six years. Marta, the oldest known common gull in the world was breeding in Kakrarahu colony in 2015. She has born in Kakrarahu colony on 3rd of June 1981 and is now 34 years old. Her father was also born and bred in this colony (1973-1989), as well as her grandfather and grandmother (bred in 1966-1980). Marta’s first and second  partnerships lasted seven and one year, respectively. The second partner returned to his previous partner, who missed the 1994 breeding season. Since 1995 Marta is breeding with Oskar (for 21 years now!), who is eight years younger (born in 1989). Altogether Marta has laid 86 eggs and 59 chicks have hatched. For now, her ten children (6 males and 4 females), eleven grandchildren (6 males and 5 females) and three grandgrandchildren (all males) have returned to breed in Kakrarahu colony. Marta is wintering on the River Severn at Purton, England (51º44’ N 2º26’ W).


The first collared bull elk is doing well


In September the very first bull elk was equipped with a satellite-telemetric monitoring collar. This tracing device will give the mammalologists of the wildlife monitoring department of the Environment Agency necessary data about the whereabouts, habitat utilization, behavioral ecology etc. 
The tracing subject was caught in the Soomaa National Park and during the next months it has moved around in the Park, albeit changed the location from one edge to the other. The main reason of active movements in the autumn is the hunting season. The traced elk is usually moving around in the radius of 10 km. The monitoring device is spotting the animal every 4th hour while the coordinates are sent to the main server of the team. Local hunters are also briefed about the elk with a wide and bright white collar, clearly visible in the twilight as well.
The wildlife monitoring team is planning to put the tracing collars all together to 10 elks. Now, when there is much more snow, it becomes possible to follow and catch the animals with a snow mobile.

Photo: Marko Kübarsepp /
Source: www.keskkonnaagentuur.ee

When the animals are already collared and thoroughly monitored, it will be possible to research their abundance or physiology as well, e.g. their endoparasites from their droppings etc.
So far the Environment Agency has used collars to monitor Roe Deer, Wild Boar, Lynx and Wolf.

Badger's life scrutinised


Second year already there's a webcamera near a badgers' town, so people have had good possibility to watch their life through internet. What was soon revealed, that just opposite the commonplace imagination, badgers are by no means twilight and night animals. Zoologist Tiit Hunt assured that morning, midday and afternoon are equally good for these positively active animals to be in the picture. 

European badger / Source: maaleht.delfi.ee

Due to the fact that although we recognize continuously increasing number of badgers in Estonia, we only know very generally that they occupy almost the whole mainland area and the Saaremaa island, but any insight into their population ecology is missing. Therefore Badger was attributed the title of the Animal of the Year 2016. Badger is the 4th mammal, who has earned such special attention. In the former years the Wolf, the Ringed Seal and the Wild Boar have earned similar attention. There are comprehensive plans to start to gather thorough data about Badger next year.

Badger is mating in June and July, so the cubs are born in March and April, although Mother Badger is able to regulate the exact springing time according to certain circumstances, explained Tiit Hunt. It may happen that the offspring have to wait for relatively long time in their Mummy's womb. Similarly to the Bear badgers also mate every second year. It takes a month until their eyes open and a next month before they start to waddle around their den. 

June 25 this year happened to be a certain top record day. Zoologists were witnessing extraordinarily long mating activity of the badger couple, all together 90 minutes, that is the longest known act in the World!

Badger camera recordings here