think the idea behind the manuscript is compelling, but I had quite a hard time deciding whether all of the analysis was based on sufficient field data to justify the conclusions. I’m honestly not sure that it was, so anything the authors could do to ground their models in the field observations themselves would be welcome.
For example, how many birds are the estimates of dispersal distance based on? The authors imply that it is not many, but I did not get the sample size-it may be there, but I would suggest it be front and center in the results or in the paragraph describing the field methods.
The major results of the paper hinge on the categorization of individuals as long-distance immigrants. How many individual birds were actually inferred to be long-distance immigrants? Is there any way to plot the actual number of inferred long distance migrants from each patch on Figure 3?

Minor comment:
Line 83 I don’t understand why this is true. A small patch may be high quality but have a lower carrying capacity than a larger, but lower-quality patch, right? I can see where density would be highest on the highest-quality patches, but not necessarily carrying capacity. I think some clarification and/or a reference here would be helpful.