Varied Thrush – Ixoreus naevius

BirdWeb – Varied Thrush

So we all know that what we know as the Robin is really the American Thrush? After our wild snowstorm (November 26, 2006)we set up our regular winter feeding station. And we watched the regular winter visitors – juncos – chickadees and such.

And so when the red breasted bird showed up I thought robin. And then I saw that there was kind of a checked pattern to the tail. Spotted Towhee and then he turned and I saw a dark collar. Not a Towhee – one of the birds that are new to me since I came out to Washington.

So off to the web and clearly a Varied Thrush after some sleuthing. This thrush is common but rarely seen. It loves the underbrush and wilds of forested areas unlike its near neighbour that thrives on urban and suburban lawns. I got some lovely pictures.

 


Balancing Business and Ecology…

ScienceDaily: Mixing Exploitation And Conservation: A Recipe For Disaster

Near and dear to my heart are those stories and studies that look at finding the balance between human survival – business and the ecosystem in which they exist. This study was done in Holland with an exquisitely ecosystem adapted bird. The red knot is a sandpiper like bird that depends on cockles to fuel its travels. 50% of the population flies through a small area. Harvesting the cockles using suction dredging is harming the population is the conclusion.

A couple of things that came to mind as I read the study. One of the important findings was that the density of cockles wasn’t changing in the dredged area. Now this might be considered an important indicator that the harvest was indeed sustainable. The kicker is that the nutritional value was going down. The result was that the a portion of the red knot population couldn’t eat enough to get the energy they needed for migration.

The second thing that rang through my mind was something a forester friend said to me as we negotiated land use for his employer. The problem with the environmentalists “ecosystem approach” to planning is that it doesn’t take into consideration the largest user on the land – man. His schtick was that we needed think about the impacts that man had on the land. Not to stop them – necessarily but to consider and plan for them – try to see all the impacts and plan for them.

A note to the reader. While I intend to focus on the particular species and ecology of the San Juans – I also want to use this space to bring in issues and information from across the globe that will impact this fragile space. Feel free to tell me to take a hike. That’s what comments are for.

 


Orcas on the Edge – National Wildlife Magazine

Orcas on the Edge – National Wildlife Magazine

This little gem caught my eye while I was browsing my email. Part of a typically well orchestrated campaign by the National Wildlife Foundation – the email was asking my support in Adopting an Orca!

Good idea or not. Is it true? Are the orca really within a 100 years of extinction? What about the salmon that they feed on? The email pointed out that this combined with global warming, toxic pollution, and vessel noise are all contributing factors.

And I sit and think of the one line from the Whale Museum visit that I made this summer that has stuck with me. In the context of talking about why orca go to certain beachs and rub themselves on the gravel. “We don’t know why.”

There is so much about these magnificent creatures that indeed we don’t know. One thing we do know though – they are a part of an intricate web of life that throbs and thrills throughout the Salish Sea and its archipelago. If I needed inspiration to encourage me in exploring this web this is it.

 


Simple Orca sociology

When I started reading about Orcinus orca I was pleasantly surprised. They are all over. Very much a symbol of the islands. The house down the street is “Orca Villa”. Bumper stickers. Sports teams. But as I started reading I was quickly fascinated by a couple of things. How recent a lot of the knowledge of orcas is. How little we know about what they do underwater and at night. And what we know about their sociology.

Out at Point Roberts I had seen for the first time the identification charts and realized that there are few enough individuals that we can learn to recognize them. What I hadn’t realized was that there are three distinct societies of whales. Distinct enough that some feel that they should be separated into races. The ones that we see most often in the San Juans are the Southern Residents. But there are transients and offshore groups as well. And there are the Northern Residents.
Resident

  • Salmon eaters
  • Larger pods (6 to 50)
  • Smaller home area
  • Dive for 3 or 4 minutes
  • Larger range of vocalization
  • Lots of echolocation
  • Rounded dorsal tip – sharper rear angle with open saddles

Transient

  • Marine mammal eaters
  • Small pods (less than 6)
  • Dive for 5 to 7 minutes
  • Minimal vocalization
  • Pointed dorsal fin with grey saddles

Offshore

  • Salmon maybe?
  • Larger pods (25 or more)
  • Outside Puget Sound
  • Continuously rounded dorsal tip – no sharp rear angle though
  • Saddle patch gery or open

 


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