spawning aggregations be considered

[Guest]

Dr. Sadovy suggested that spawning aggregations be considered protected events rather than simply times when fish are easy to catch, as has been done with salmon in Bristol Bay, Alaska.



"as has been done with salmon in Bristol Bay, Alaska" modifies fish or spawning aggregations?

[Guest]

Sorry. My mistake.

"has" I can guess "as has been done with salmon in Bristol Bay, Alaska" modifies Dr. Sadovy

I 'm confused when "done with salmon in Bristol Bay, Alaska" rather than "as done with salmon in Bristol Bay, Alaska" is used below :

Dr. Sadovy suggested that spawning aggregations be considered protected events rather than simply times when fish are easy to catch, as done with salmon in Bristol Bay, Alaska.

Thanks.

[JonathanSchneider]

You would want the first choice, to retain parallelism:
"Be considered" --- "been done"