There should be a "Presumption in Favour of Development" therefore taken literally development should happen unless it can be proven that there will be an impact. In this case there is only the suggestion.
I was a former town planner for a private consultant and had similar problems when looking at increasing the number of days a local motor racing circuit (Bishopscourt) could operate (Bishopscourt was a former RAF airfield and had a long history of motorsport on the site).
The planners refused to consider an extension due to impact on residents and wildlife (badgers) even though the badgers were fine with the racing on the 16 other days of the year, and most of the residents actually supported the development,. Those that didnt were "blow ins" who moved into the area and didnt like the racing circuit. I am not sure exactly what happened in the end as i left for another company.
Back to your initial question regarding birds. The RSPB have a bird sanctuary with hides etc within 700m of the runway centreline of Belfast City Airport (EGAC). Belfast Lough is also an ASSI. https://www.rspb.org.uk/reserves-and-ev ... fastlough/
There is also Victoria Park at the approach to Runway 04 which on the Belfast City Council website is described as having a rich Diversity of Wildlife.
Then there is my home airfield (Newtownards EGAD) which is within Strangford Lough AONB. Strangford Lough is Northern Ireland’s first marine nature reserve and is the British Isles’ largest sea inlet, internationally renowned for its marine, plant and wildlife.
There is also Castle Espie (Castle Espie is a wetland reserve managed by the Wildfowl and Wetlands Trust on the banks of Strangford Lough) which is located aprrox 1 mile outside the Newtownards ATZ. http://www.wwt.org.uk/wetland-centres/castle-espie/
Hope that helps.