Plants and Animals

How old was our eucalypt when it died in 2008?

Although frequently promoting trees as evidence of current climate change, it’s been my view for a while that the science of “dating” any specimen’s history via its growth rings, must account for extended droughts and abrupt climate disturbances such as flash flooding.

This example from yesterday’s street saga is no exception given the ACT region’s recent rainfall patterns.

I reckon our study in harsh climates also depends on the performance of particular roots over time.

Gavin.

All good things must come to an end. Yesterday the tree surgeons moved in with their trucks, cherry picker and mobile chipper but the birds had moved back. A hasty roadside conference followed phone calls to base and several door knockings. The high drama was supervised all morning from above by currawongs, suburban pests by my reckoning.

Frogmouths resisting “arrest” had to be witnessed. Despite a very noisy and finally violent intrusion my owls demonstrated a distinct preference for our late street tree with its dead canopy hiding their daytime roost, a rough barked E. nicholii. Other mature trees in the street are the local white barked E. mannifera and smooth barked E. melliodora.

With a chainsaw running downstairs, common sense prevailed. After tapping their perch with a long stick from the aerial platform failed, the tree was shaken from the top down. The birds reluctantly hopped to higher branches then perched again, just out of reach.

With time patience running out on both sides an extra violent movement or two eventually dislodged them both. They flew off independently to neighbouring trees but were now split up on either side of the street. The dead tree was immediately felled in large pieces, completely mulched and the road side all swept up before smoko.

It seems urban safety programs and taxpayer’s funds are well protected. Note how the frogmouth displays a “stiff upper lip” next door as their temporary home disappears.

Gavin.

http://en.wikipedia.org/wiki/Currawong

http://www.anbg.gov.au/gnp/gnp7/eucalyptus-mannifera.html

http://en.wikipedia.org/wiki/Flora_of_the_Australian_Capital_Territory

ANCHORAGE, Alaska — A federal judge has ordered the Interior Department to decide within 16 days whether polar bears should be listed as a threatened species because of global warming.

The ruling is a victory for conservation groups that claim the Bush administration has delayed a polar bear decision to avoid addressing global warming and to avoid roadblocks to development such as the transfer of offshore petroleum leases in the Chukchi Sea off Alaska’s northwest coast to oil company bidders.

“We hope that this decision marks the end of the Bush administration’s delays and denial so that immediate action may be taken to protect polar bears from extinction,” Greenpeace representative Melanie Duchin said in a statement.

The Seattle Times: Judge orders federal government to decide polar bear listing

Polar bears in Canada are at risk from climate change but not threatened with extinction, a panel of accutane experts has advised the Canadian government.

The government should develop a plan to protect the country’s estimated 15,000 polar bears, the panel said.

The animals face loss of habitat on two fronts, the panel said – hunting, and melting ice in the Arctic, which is widely blamed on climate change.

BBC News: Polar bears ‘at risk’ in Canada

A former resident of Canberra complained today on talkback radio about how the city had become “tatty” during her brief absence. Apparently her family now lives somewhere up the north coast and have green lawns. The difference I reckoned was that the ACT region has missed out again in late autumn with our miserable share of La Nina.

Out on the western fringe of suburbia a few local residents have been watching two strange visitors for a week or so. Opposite my place is another dead tree, a large Eucalyptus nicholii that was planted as a street tree back in the early 1970’s. A few bird droppings on parked cars was the first clue. My neighbor pointed up to some high branches and eventually I recognized the shapes, a pair (?) of tawny frogmouths perched motionless in the higher branches.

This messy old tree would normally have been condemned as a neighborhood hazard and removed on schedule with many others, however overnight it became “habitat” for what I believe after glimpsing another big wary gray bird on the outer limb late yesterday, two young owls left day by day by their parents.

Despite prying eyes, noisy cars, trucks and machinery underneath these beautifully camouflaged individuals remained seemingly motionless for days. Unfortunately I think a gang of currawongs has finally driven them off.

Note the clear blue sky in my latest photo.

Gavin

Funny, the things that you see in nature, like this humanoid face on the cephalothorax of a golden orb-weaver, Nephila pilipes.

I have previously described aspects of this spectacular species of spider, here and here. With this instalment, the adult female in the image below descended from her web on the 19th April to build her egg-sac on the ceramic-tiled floor of our living room.

At the outset, her abdomen was rotund, perhaps twice the diameter of the largest aspect within the image captured at the conclusion of the construction.

On a foundation bed of the same orange silk that can be seen, a white disk was established and then encased in more of the orange material. Five weeks later, the orange casing had lifted. The white disc had been abandoned, but its character was surprisingly hard; rather like coral in its chalky-porousness. I can only imagine that it was produced in much the same way as a mantid’s ootheca – soft upon release but hardened under external exposure.

It had been my understanding that egg-laying was the final phase in the three-month life-cycle of this species, but this individual struggled back to the ceiling and over a succession of days manged to rebuild a small web. Aided by the sympathies of my children, a number of march flies allowed for a fuller recovery and the re-establishment of a master-web. She lived another month and then presumably underwent a second and final reproductive cycle.

“This due to their campaigns against whaling and sealing. Their campaigns are against a reasonable and sustainable harvesting of marine resources,” states the Head of the Norwegian Fishermen’s Union, Reidar Nilsen, yesterday in paper, Fiskeribladet Fiskaren.

His reply was a response to WWF Norway that had made statements that the fishermen overfished the marine resources and thus were a threat to the world’s food resources, but Nilsen said the NGOs are a bigger threat to the world’s food resources through their anti whaling and anti sealing actions. According to Nilsen, it was in the fishermen’s own interest to conserve and harvest marine resources in a responsible way.

It seems as well that Mr. Nilsen’s statement has not as much to do with eating whale and seal meat but again as an “whales eat too much fish” argument. Nilson states that the whales are consuming 4 or 5 times as much fish than the fishermen are harvesting.

According to Norwegian animal welfare organisation, Dyrebeskyttelsen, It’s wrong to make scapegoats of the whales. They state, “The whales belong in the eco system, and that the fish the whales are eating are brought back to the eco system. Humans on the contrary are removing both fish and marine mammals from the system.”

We have also heard that the Norwegian IWC Commissioner, Mr. Klepsvik , has stated that the Norwegians are managing their marine resources in a holistic approach, meaning if they take out fish from the seas, they must also harvest whales.

Cheers,
Ann
Sweden