Tannin
Storage? I am Storage!
I'm not sure about the egg size, I'll look it up later on today at Belinda's (we keep all our bird books at her place, because that's where the birds are).
So far, so good. The current six-year drought is severe in Australia generally, but we have been lucky: so far there has been no real damage, as we have had just enough rain to keep the surface moist. Trouble is, the sub-soil just has nothing left in it, so this summer could be a complete disaster. Belinda's damn is at its lowest level ever, and the summer hasn't even started yet. (In late spring, after the winter rains, it should be full.)
I had no idea that California was having one too, Buck, though I should have guessed it from reading about your bad fire seasons lately. I am a little surprised to hear about insect eating birds disappearing. It seems odd to me; I would have expected it to be the nectar-feeding ones. After all, the amount of nectar substitute that humans provide must be tiny by comparison with the natural supply, except in the confines of suburban areas, of course. Over here I know that the price of honey has roughly doubled because there just isn't enough nectar for the bees to make their usual amount. (Again, our particular part of the world is much more mildly affected so far than places as little as 50k further north.) But, if anything, we have seen an increase in the number of insect feeding birds. Let me see, there are blackbirds (imported vermin species from England, but they are here), grey thrush, blue wren, red robin, golden whistler, rufous whistler, white-throated tree-creeper, grey fantail, spotted pardalote, striated pardalote, brown thornbill, striated thornbill. magpie, mudlark, silvereye, doubtless some others that escape me at the moment (it's 5:00AM here so I'm not going to ring Belinda to jog my memory!). These are all the usual suspects, and they are in their usual numbers, perhaps more than ever. No sign yet of the flycatchers, but it's a little early in the year for them yet. Also this last year or so, we have had at least four ones that used to just pass through on their way from one place to another move in and set up house: yellow robin, yellow thornbill, crested shrike-tit, scrub-wren.
So why is it that you have a drought and fewer insectivorous birds, and we have a drought and more of them? I have a couple of theories: (a) the high summer is yet to hit and grim times lie ahead for us; (b) the worst of the drought is elsewhere and, so far, we are insulated from it. (c) Australian insects are better adapted to drought, and there is still just as much to eat this year as there is in a good year.
On theory (b) its worth noting that there are some seasonal migrants that are always a sign of dry further north, in particular the grass parrots, which usually arrive in summer to feast on eucalypt nectar, but arrive in far greater numbers when it's dry up north - and last year, as witness Tea's post in the China Thread, they were here in numbers. Perhaps some of our recent insectivorous arrivals are refugees too.
On theory (c), I'm sure that there is truth in this. ENSO has been a part of the climate here for a very long time, probably some millions of years, so drought is something that every single species in Australia is adapted to - or was adapted to, as we humans have made three seperate changes that are making things difficult: (a) global climate change; (b) habitat destruction: by removing particular parts of the place in accordance with what we happen to find convenient for farming and building on, we have forced many species into areas that are marginal for their needs - OK in a good year but unsuitable to support life in a bad year. and (c) habitat fragmentation: by reducing and eliminating the connections between the remaining islands of natural vegetation, we make it difficult or impossible for many species to migrate to more suitable areas when conditions change. The ability of different species to follow the seasons and the rains varies, of course. My favourite example is the silvereye: a tiny little thing the size of a large hummingbird (I should say "two-thirds the size of a sparrow", as I'm not sure how big hummers get) which eats insects, fruit, and seeds, whichever happens to be most convenient, and which, as a matter of routine, crosses Bass Strait - that's 200 miles of ocean!
So far, so good. The current six-year drought is severe in Australia generally, but we have been lucky: so far there has been no real damage, as we have had just enough rain to keep the surface moist. Trouble is, the sub-soil just has nothing left in it, so this summer could be a complete disaster. Belinda's damn is at its lowest level ever, and the summer hasn't even started yet. (In late spring, after the winter rains, it should be full.)
I had no idea that California was having one too, Buck, though I should have guessed it from reading about your bad fire seasons lately. I am a little surprised to hear about insect eating birds disappearing. It seems odd to me; I would have expected it to be the nectar-feeding ones. After all, the amount of nectar substitute that humans provide must be tiny by comparison with the natural supply, except in the confines of suburban areas, of course. Over here I know that the price of honey has roughly doubled because there just isn't enough nectar for the bees to make their usual amount. (Again, our particular part of the world is much more mildly affected so far than places as little as 50k further north.) But, if anything, we have seen an increase in the number of insect feeding birds. Let me see, there are blackbirds (imported vermin species from England, but they are here), grey thrush, blue wren, red robin, golden whistler, rufous whistler, white-throated tree-creeper, grey fantail, spotted pardalote, striated pardalote, brown thornbill, striated thornbill. magpie, mudlark, silvereye, doubtless some others that escape me at the moment (it's 5:00AM here so I'm not going to ring Belinda to jog my memory!). These are all the usual suspects, and they are in their usual numbers, perhaps more than ever. No sign yet of the flycatchers, but it's a little early in the year for them yet. Also this last year or so, we have had at least four ones that used to just pass through on their way from one place to another move in and set up house: yellow robin, yellow thornbill, crested shrike-tit, scrub-wren.
So why is it that you have a drought and fewer insectivorous birds, and we have a drought and more of them? I have a couple of theories: (a) the high summer is yet to hit and grim times lie ahead for us; (b) the worst of the drought is elsewhere and, so far, we are insulated from it. (c) Australian insects are better adapted to drought, and there is still just as much to eat this year as there is in a good year.
On theory (b) its worth noting that there are some seasonal migrants that are always a sign of dry further north, in particular the grass parrots, which usually arrive in summer to feast on eucalypt nectar, but arrive in far greater numbers when it's dry up north - and last year, as witness Tea's post in the China Thread, they were here in numbers. Perhaps some of our recent insectivorous arrivals are refugees too.
On theory (c), I'm sure that there is truth in this. ENSO has been a part of the climate here for a very long time, probably some millions of years, so drought is something that every single species in Australia is adapted to - or was adapted to, as we humans have made three seperate changes that are making things difficult: (a) global climate change; (b) habitat destruction: by removing particular parts of the place in accordance with what we happen to find convenient for farming and building on, we have forced many species into areas that are marginal for their needs - OK in a good year but unsuitable to support life in a bad year. and (c) habitat fragmentation: by reducing and eliminating the connections between the remaining islands of natural vegetation, we make it difficult or impossible for many species to migrate to more suitable areas when conditions change. The ability of different species to follow the seasons and the rains varies, of course. My favourite example is the silvereye: a tiny little thing the size of a large hummingbird (I should say "two-thirds the size of a sparrow", as I'm not sure how big hummers get) which eats insects, fruit, and seeds, whichever happens to be most convenient, and which, as a matter of routine, crosses Bass Strait - that's 200 miles of ocean!