I suspect (ii) are not doing well either. Since 1970 sweeping changes in farmland management have been undertaken in the USA, as across the world. Numbers of Red-Legged Partridge have dropped by ~75% in a decade in France, for example. Declines in insects have greatly reduced insectivorous species, while glyphosate is ubiquitous, and foliage is doused in it, affecting herbivores. If it weren't for hedgerows/windbreaks, we'd have no birds at all in Iowa and Nebraska, I reckon.

When haying was done by hand, birds nesting on clutches of young hidden in the grass were able to flee the scythe. The only species that survive today are those that do not do so, as mechanical harvest of grasses does not afford them a chance to escape anymore. [I am not advocating returning to hand mowing. Just raising the blades to 6" or so, which leaves enough depth of stubble to allow almost all birds to survive by crouching, an instinctive reaction of prey species].

Glad to know I have been an impetus to think.

Thanks!