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by da39a3ee 997 days ago
If you were to ask a migratory bird, they'd tell you that it's fairly tough. You have to put on enough subcutaneous fat to double your body weight, and then do it knowing that either you or some of your friends and family will die.
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Also, with global warming and stuff, if possible those birds migrate less.
There is no evidence to support this statement.
Plenty ofnevidence, of e.g. geese, migrating tonplaces further north. But surey birds don't exist anyway.
Please provide your sources for the effect of climate change on bird migration.
I'm sorry if it wasn't clear, but I was asking for sources on GP's claim that climate change has shifted the north-south spatial location of birds' migration destinations.

The research you linked to doesn't seem to be saying that; it's claims are about the influence of interannual climate variation on timing of migration IIUC.

-- https://journals.ametsoc.org/view/journals/bams/103/2/BAMS-D...

Abstract For ∼100 years, the continental patterns of avian migration in North America have been described in the context of three or four primary flyways. This spatial compartmentalization often fails to adequately reflect a critical characterization of migration—phenology. This shortcoming has been partly due to the lack of reliable continental-scale data, a gap filled by our current study. Here, we leveraged unique radar-based data quantifying migration phenology and used an objective regionalization approach to introduce a new spatial framework that reflects interannual variability. Therefore, the resulting spatial classification is intrinsically different from the “flyway concept.” We identified two regions with distinct interannual variability of spring migration across the contiguous United States. This data-driven framework enabled us to explore the climatic cues affecting the interannual variability of migration phenology, “specific to each region” across North America. For example, our “two-region” approach allowed us to identify an east–west dipole pattern in migratory behavior linked to atmospheric Rossby waves. Also, we revealed that migration movements over the western United States were inversely related to interannual and low-frequency variability of regional temperature. A similar link, but weaker and only for interannual variability, was evident for the eastern region. However, this region was more strongly tied to climate teleconnections, particularly to the east Pacific–North Pacific (EP–NP) pattern. The results suggest that oceanic forcing in the tropical Pacific—through a chain of processes including Rossby wave trains—controls the climatic conditions, associated with bird migration over the eastern United States. Our spatial platform would facilitate better understanding of the mechanisms responsible for broadscale migration phenology and its potential future changes.

'may in the future ' basically...