Quite a few birds make burrows for nesting. Very few live in them when not nesting, and all have to come out every day to look for food. I don’t think any store food in them like small mammals do.
Something that puzzles me - were there no dinosaurs occupying a similar evolutionary niche as crocodiles? Had the crocodiles already outcompeted all the dinosaurs in shallow water environments?
I would think that would kill anything for the survivors to eat. There might have been some worms and burrowing insects.
Errr…other way around. The gap between T-Rex and Stegos is 20 million years larger than the gap between us and T-Rex.
It is wrong, but nit-pickingly closer to correct, to show humans living beside T-Rex than to show T-Rex living beside Stegosaurus.
Which behavior do you mean? Eating fish, or waiting to ambush land animals that are attempting to drink water? The spinosaurs probably were the closest that we know of.
Whichever behaviour it was that enabled (some?) crocodiles to survive.
Even with crocs, half of the families didn’t survive and no large ones.
That’s unlikely. Apart from anything else, while Australia and New Zealand have KT sediment strata, we have yet to find a single plant which went extinct there.
The spinosaurs, however, died out a good 20 million years before the KT event.
Dinosaurs may not have evolved to fill the crocodile niche because the crocodiles were already filling it.
Perhaps they ate anything that tried.
Some birds might have survived, not by burrowing, but by living in (or just happening to be over at the time) large bodies of water sufficiently far from anything flammable.
Mammals also came close to not making it, with possibly over 90 percent of species going extinct.
The largest Mesozoic crocodiles were in the size range of mid-sized dinosaurs and most likely preyed on ones that got too close to the water.
Four lineages of birds appear to have survived the extinction event: ostrich-like birds, or ratites, whose ancestors were probably flying forms at the time; chicken-like birds; ducks; and the ancestors of all other modern birds. It seems the ancestors of the last were mainly marine or aquatic at the time.
Why did the chicken cross the road?
The escape the K-T extinction event.
If we’re at this point…
Life DIDN’T find a way?
“Life” created us, and sooner or later we’ll figure out a way to bring them back! 
In truth, there is no known factual answer to the OP’s question. If someone knows, they should quickly publish their findings in one of the appropriate journals. People in this thread are certainly offering plausible, intelligent explanations, but the truth is that we are just not certain. Due to the difficulty in testing hypothesis, it’s likely that we may never know in the way we “know” other things in science, like why the planets orbit around the sun.
I would like to see this boundary. I started a thread once asking where to do so.
They don’t. They orbit around the Earth, in a very weird fashion.
Or, if you prefer, the Sun orbits around each of them at the same time.
Need to pick some other hypothesis which can actually be tested. :rolleyes:
This site suggests Raton Basin, in Colorado and New Mexico.