Friday, February 7, 2014

Myth Busting ?! - Grebes and Scoters

If everyone else can state opinion like fact, I can too! (Right?)

These theories sound really great, and they pop up year after year.... Are Red-necked Grebes, Horned Grebes, Red-throated Loons, Long-tailed Ducks and White-winged Scoters (among other waterfowl) - being "frozen out" of the Great Lakes?

See here for the usual story:

SO what's my opinion, theory, guess, absolute factual take on the situation? 

They are MIGRATING NORTH for cryin out loud....

Let's look at some basic trains of thought -

Lake Erie froze - therefore Grebes are being pushed out? - NO I say! - How many grebes even winter on the Great Lakes? Remarkably few I would think!

The Great Lakes are freezing overall? - that theory makes no sense for all of these species (as noted above) - but especially Long-tailed Ducks and White-winged Scoters. The MAIN wintering area for these species is Lake Ontario - which has very little ice! It rarely freezes over, and even when ice does form - it rarely lasts for more than 12 hours. 

Grebes are being grounded in bad weather inland! Save them! - why would these Grebes be leaving ice-covered lakes during a storm? Stormy weather breaks up ice, it rarely "creates" it - it's usually after a storm - during the cold that follows - that ice forms - meaning the birds would have clear skies and an epic tailwind to leave the great lakes with ease! While it works both ways (spring or fall migrant) - these birds sure look like they were leaving the east coast and travelling inland when they hit poor weather and were grounded...

All of these species also winter pretty darn close... Check out ebird maps - all from the east coast, and they all state in huge numbers on the great lakes in spring... All of which (esp Red-throated Loon and RN Grebe) will see their numbers continue to climb steadily in the next few weeks to months as more arrive. RT Loon especially often has decent concentrations near the mouth of the Niagara River in early spring. 

How dare anyone ever accuse this species of fleeing cold and ice!

Anyways - I just wanted to throw my 2 cents out there... I DO think that the abnormal amount of ice will concentrate birds and increase the detection rate - but I do NOT think they are fleeing our climes. Spring is darn close - it's February for cryin out loud!

Next up - RN Ducks, Geese, Tundra Swans, and maybe Pintail! 


  1. Hey Brandon- I agree that the freeze-out theory sounded good when I first heard about it ten years ago, but then over the years it didn't seem to make much sense. It seems like some years esp those with little shore ice through mid-Jan, you can go out and see RT Loons, RN Grebes, and Horned Grebes at known locations along the south Lake Ontario shore (ie. thru winter). Years with a lot of shore ice these birds are not present, and likely leave to the southeast/coast. BUT the deal is that given shore ice or no ice, they are always starting to increase/appear in larger numbers starting mid-Feb onwards, and are no doubt birds returning north at this time. And for the record, has the ice cover really changed that drastically across the GLs from late Dec this year till now? There's been a lot of ice out there for weeks on end. The birds would have reacted to it a while ago if that was really the reason for their appearance. -JP

    1. I don't think there has really been any major changes in ice cover for Lakes Erie and Ontario over the past several weeks - so that fits our thoughts quite well.. Superior and Huron have had dramatic freeze-up's over the past several days, but that was after the ducks/grebes started showing up!