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I would have though so, too. Fortunately, the good doctors answered the question at the end of the piece:

But crocodiles and turtles had already evolved at the time of the great extinction 65 million years ago. How did they survive?

"These animals live at the intersection of aquatic and terrestrial environments, in estuarine waters and river beds, which might have afforded some protection against the more extreme effects of environmental change, hence giving them more time to adapt," the researchers wrote.

Why did the Ichtysaurs (sp?) die out, then? Wouldn't they have also benefited from living in the oceans?

The crocodilian survival aspect can be explained by how they lay their eggs. The basically dig a hole, and with some micro-thermoreceptor holes at the bottom of their lower jaw (they look like small beauty spots) register the ambient heat. They lay their eggs, and then careful cover the hole with dirt, before covering it some more with leaves. The decaying leaves have a compost effect, which maintains the heat (and depending on how deep the eggs are laid, the temperature differences cause some to be male and others female, with hotter eggs being male and cooler eggs being female).

Hence the eggs would have survived a global cooling caused by the dust thrown up in the asteroid hit.

And consequently, the reason of crocodilians surviving because of living in the intersection of land and water is moot. Why? Because if that was the case then aquatic species of dinosaur would have also survived the cooling! (Although the LochNess/lake Champ 'witnesses' would claim Nessie and Champ are aquatic dinosaurs ....but i won't go there).

In my opinion, in the event of an asteroid hit churning up dust, the only thing that would have saved crocodilians and turtles is their habit of thermo-regulating their eggs by burrying them in earth. And certainly not to them living where earth and water meet, because if that theory was true swimming in lakes and oceans today may lead to a mano-a-mano meet with 40 feet of swimming scales and teeth with a name ending with 'saurus.'

Spetz's theory: laying the eggs in holes covered with earth and decaying compost saced the crocodilians. Water and earth meeting had little or no effect whatsoever, and if the crocodiles laid their eggs and left them in the sun (as the dinosaurs probably did) the cooler temperatures would have done them in too. Remember the eruption of some mountain in the 1800s that caused winter to last for a whole year (the funny thing is that scientists then were blaming it on 'experiments with electricity' and on lightning rods 'stealing heat from the sky' when the real cause was a violent eruption sending ash that effectively cooled the whole earth).

Now, to get a timemachine so as to see if that is as it happened!