Month: September 2009

Castor CSI

heidi08 In the News September 25, 2009

More From our Foreign Correspondent: Alex Hiller

Susanne Horne Max Planke Molecular Ecology

Criminal Intent on beaver fossils:

How can you be sure the injured beaver from the road shoulder is not a stranger in the night but legally belongs to its geographical habitat? – Just show a tissue sample to Susanne Horn at Max-Planck-Institute for Evolutionary Anthropology in Leipzig, Germany and get its DNA analyzed.

In her lecture she mentioned a DNA probe of an injured beaver recognizing it as member of the inherent Eurasian beaver species Castor fiber and not of the North American species Castor canadensis it was suspected to be according to the untypical color of its anal gland secretion. DNA research was done on the data basis taken from dozens of tooth and bone samples of ancient beavers throughout Europe.

Beaver Populations can be distinguished even locally by the genetic DNA sequences. Extensive hunt in the 19th century had led to the extirpation of beaver in most parts of Europe except for a few relict populations thus providing a bottleneck in the genetic diversity.

According to the Symposium`s student award winner of the 2nd price, Susanne Horn, “ancient DNA can provide information on the indigenous beavers of a certain area. These results reflecting the history of this species, can now be taken into account by maintenance projects, when planning the relocation of beavers.

Speaking of anal gland secretion (AGS) the 1st price of the student’s award was won by students from Telemark University College, Bo, Norway, on investigation “whether information about age and territory ownership (social status) is coded in the AGS of male Euroasian beavers” ( c.fiber ). Experimental scent mounts in a field study using a free ranging population in Telemark, Norway, as well as chemical analysis confirmed the preliminary suggestions: The older son of a male intruder appeared to pose a greater threat to resident beavers than the younger son and the intruder itself, suggesting “that dominant beavers carry a `territory owner`badge making them perceived as less a threat than beavers without a territory. ( Helga Veronika Tinnesand, Susan Jojola, Frank Rosell )

Regarding beaver territory the participants of the Symposium were shown the findings at a prehistorical beaver site and its suggestions on the development of the beaver species:

Excavations at an ancient peat bog on utmost northern Canadian Ellesmere Island disclosed in its permafrost ground well preserved bones, sculls, claws and teeth of prehistorical beavers as well as hundreds of sizzled sticks with teeth marks at age of 3 to 5 millions of years ago (in short = mya ) just before Ice Age. Natalia Rybczynski of Canadian Museum of Nature, Ottawa, who led the excavations, did research on the form follows function relationship regarding ( 1 ) swimming, ( 2 ) grooming claw and ( 3 ) woodcutting .

Rybcynski`s findings to ( 1 ) were, that the stream-line body , its modified webbed hind feet and modified tail developed 23 mya with its tail as a “propulsive structure” while swimming for getting thrust. The specific form of a flattened tail developed only 5 to 10 mya whereas the ancient grooming claws ( 2 ) had presumably developed 30 to 35 mya and could be distinguished easily by their specific shape different from regular claws at hands and feet throughout millions of years. Woodcutting behavior ( 3 ) could be proved by investigations in National Zoo of Washington, DC: Video analysis of beaver teeth in action cutting wood gave evidence that beaver make use only of one incisor in adjacent position at one side of their jaws, that means beaver gnaw sidewards providing a mean cut width of 60 % of Incisor width. Exactly the same pattern was analyzed on the sizzled sticks of 3 to 5 mya from Ellesmere Island. As a result wood-cutting behavior in beavers is presumed to have developed 23 mya. What still remains to be unsolved according to Rybczinski is the development of dam-building behavior of beavers.

Sticking to the teeth of beaver fossils, Dr. Clara Stefen, Curator of Mammals at Senckenberg Museum of Natural History , Dresden, Germany, presented her research on length to width ratios of upper and lower molars of beaver sculls to determine the evolutionary progress.

Best

Alex Hiller

Meet Glynnis Hood

heidi08 Creative Solutions, Educational, Environmental September 24, 2009

Another presenter at the beaver symposium, and a favorite of Alex and myself, Glynnis has done important research on the effects of beavers on drought conditions and the environment.

“Removal of beaver should be considered an environmental disturbance on par with in-filling, peat mining and industrial water extraction,” said researcher Glynnis Hood, lead author on the study and an assistant professor of Environmental Sciences at the University of Alberta’s Augustana Campus in Camrose, Canada.

Ahhh Glynnis, we need to send YOU a t-shirt next! I guess those beavers in canada are doing something besides holding down the backs of nickles.

“In times of drought they may be one of the most effective ways to mitigate wetland loss,” said Hood. “Some people believe climate is driving everything, but the presence of beaver has a dramatic effect on the availability of open water in an area. Beaver are helping to keep water in areas that would otherwise be dry.” Even during drought, where beaver were present, there was 60 per cent more open water than those same areas during previous drought periods when beaver were absent.

Here are some other presenters at the conference, Dr. Peter Bush from Boston University, that Alex posted about yesterday.

Obviously Massachusetts is a hotbed of beaver thinking. Today our old friend Mike Callahan of Beaver Solutions is on his way to the state house to do some presentations on beavers for the MSPCA. Good luck Mike!

You’ll probably recognize this other presenter with no introduction…

Alex! We are so grateful to you for this sneak peak at the world’s best beaver minds! Stay tuned tomorrow for the first ever episode of “Castor CSI” where beaver DNA will provide starting insights into foul play…

Our Correspondent in the Field…

heidi08 New Species September 25, 2009

Skip Lisle & Alex Hiller at 2009 Beaver Conference in Lithuania

Hi Heidi,

you are receiving the summary of the first lecture day – September 21, 2009, – at the 5th international Beaver Symposium. I had to solve unexpected difficulties in getting Internet access. Proudly wearing your “Worth a dam” T-Shirts Skip Lisle immediately recognized his adventures in Martinez , CA, when getting sight of me just after breakfast. Another participant from Denmark pointed at my T-Shirt telling me that he knows about it via Internet

Skip is well known to the citizens of Martinez, CA, for the construction of a “castor master” beaver dam flow device in Alhambra Creek one and a half year ago. His talk at the end of the second lecture day was the most practical and instantly useful of the whole conference. If anybody wondered what could be done about flooding problems regarding co-existence with beavers, Skip would have the proper solution at hand.

From the presentation of Peter Busher: Darwin and the elephants

“Beavers, in a population sense, can be regarded as `mini elephants`, since they are also relatively large (for rodents), long lived and have few predators (other than humans) in most natural situations.”

Prof. Peter Busher from Boston University, Massachusetts, as chairman of the scientific committee referred to Charles Darwin who developed 250 years ago on the population dynamics of elephants his evolution theory. DarwinŽs famous book “The Origin of Species by Means of Natural Selection or the Preservation of Favored Races in the Struggle for Life”was published in 1859. Moreover in 2009 it is the bicentennial of Darwin (1809 – 2009 ).

According to Busher Darwin had developed an exponential growth equation, that given one elephant cow starts calving at the age of 30 for the consecutive 60 years until death meanwhile giving birth to a calf every three years that reaches maturity itself following the same scheme we should expect 19 million elephants to live on earth within a surprisingly short period of time. In fact we know that such kind of equations cannot come true according to loss of habitat, hunting, disease, accident, wildfire, extended drought etc..

Busher insisted on long-term investigations “since any short-term study does not allow
a full understanding of the natural pattern of change in beaver populations: The general long-term pattern is one of slow initial growth, exponential growth (traditional “J” shaped curve ), decline and stabilization around a carrying capacity”.

For example the number of beaver sites in Voyagers National Park, Minnesota, increased from 50 to 360 between 1940 to 1985 whereas the number of beaver individuals throughout the entire state of Massachusetts increased from 22500 to 65000 within 8 years from 1994 to 2002 according to Busher. What was rich growth, what was poor
growth ?

Change in population size occurs regardless of the density, populations fluctuate over the time, finished Peter Busher his lecture that could be regarded as a proper measure for the numerous detailed presentations following on that topic.

Among the presentations were investigations on the reasons of population change, such as food competition among elk and beavers researched by Glynnis Hood, assistant professor at the University of Alberta, Canada:

Caused by overpopulation elk chewed down tree saplings knee high in Elk Island Park Alberta, Canada. On the contrary, according to Hood “beaver turn down a vertical forest into a horizontal” by felling trees in order to forage on leaves and twigs. It were the beavers smart enough to adapt their foraging behavior, given array of forage species, “which potentially buffers the effects of competition between elk, deer and beaver.”

Other topics of the first lecturer day were beaver biology and paleontology at the International Beaver Symposium being performed from Sept. 20 – 23, 2009, in the little eastern European country of Lithuania sited between Baltic Sea and Russian border. Mild temperatures and sunshine made it easy and comfortable to stayand socialize .

On the red pine shaded conference center at a marvelous lakeside in Dubingiai north of Lithuanian capital Vilnius 99 beaver enthusiasts of almost scientific background from all over Europe were joined by 6 leading North American beaver specialists, among them Peter Busher and Skip Lisle.

More to come!

Best
Alex Hiller

Just….wow….

heidi08 Uncategorized September 23, 2009

[youtube:http://youtube.com/watch?v=gSOqFJvxoOw]

Once Upon A Time…

heidi08 Beavers or Social Ambasadors, City Reports, Creative Solutions September 22, 2009

Once upon a time, in a very far off land where olive trees made a familiar pattern on the hills, a family of travelling magicians moved into the creek. There were three to begin with, a mother, a father and a healthy teen and all were adept at weaving straw into gold and sticks into shelters. They picked a neglected spot along the stream to make their home, right at the edge of the tide, and nestled in amongst the willows and rushes of their people.

Children and their parents sometimes stopped near their camp to watch a party trick or two. The magicians could juggle brightly colored lights and carry trees on their fingertips and it was amusing for the townspeople to see. But back at the castle, the stern old mapmaker was not amused, and argued that the magicians would call the Great Waters to rise up and flood the small village, drowning their homes and cattle. He directed the magistrate to kill the magician family, and the decision was swiftly made to execute.

‘Such decree of death caused public outcry for those who had enjoyed the magicians waterside display, and the sentence was softened to banishment when the children began to cry at the great meeting where it was considered. A gathering was planned to consider the fate of the magicians, and all the people left their huts and hovels to join in council around the fireside where important decisions were always made. There were four on the dais and four hundred in the fields. The magistrate’s brought in high priests with yardsticks to speak of the Great Flood the magicians would bring if allowed to stay, and the people spoke of their talents and treasures and asked that the magistrate find a wizard who could prevent the flood and allow the magicians to remain.

Faced with such a united and determined voice, the magistrate appointed a council of seven and charged them with the weighty task of finding such a wizard and setting him to its dilemma. Perhaps he expected the task to be impossible, and hoped to divide the inevitable failure by seven and share the blame for banishment. However, these seven quickly scoured the nation for the best skills in the land and the sharpest minds of the nation. After 90 days of searching they brought forth a great wizard the Green Mountain State and, after much council and deliberation, employed him for the position.

Sir Gallop of Lisle was tall and stern as he surveyed the magicians’ lair and considered the risks of the great flood. The pulses of many a maiden fluttered as he strode shirtless into the shallow creek to see what damage might be called. Despite the prodigious difficulties he knew just what must be done, and he used an enchanted conduit to move some of the powers from the area so that the magicians could cause no harm. With the new bypass in place, even the yardsticks of the high priests could assess no risk of flood. There was great rejoicing and many sighs of relief, and the townsfolk bought Sir Gallop many tankards of finest ale before he returned to his home in the green mountains.

Now the magicians have lived in the town for three autumns, and the townsfolk still love to gather and watch their displays. The enchanted conduit works day and night to direct the power, and in the late summer the townsfolk gather for a festival to celebrate the magicians presence in their town. Come join them some evening to watch the juggling of brightly colored lights at the waterside, and remember that your town may get magicians soon.