Well it could be either positive or negative.

If some of the coastal reclamation project is dedicated to shore bird habitat restoration then it would be quite positive.

See for instance:

https://www.restorethegulf.gov/sites/default/files/Texas%20Coast%20Migratory%20and%20Shore%20Bird%20Habitat%20Restoration.pdf

http://www.njaudubon.org/SectionResearch/Projects/StoneHarborPointRestoration.aspx

On the negative side, if coastal reclamation impacts or changes or eliminates coastal wetland regions, that will have a profound effect on the nutrient flow cycle on which most birds depend.

see

http://wh.er.usgs.gov/slr/coastalwetlands.html

The answer given above by G. Bothun makes a valid point that many coastal reclamation projects now include habitat restoration schemes to compensate for the potential adverse impacts that reclamation can have on habitats.

However, I shall assume in my answer that follows that there will be negligible habitat restoration. Impacts of reclamation will depend on the size and nature of the reclamation, the size and nature of the estuary/wetland affected and the useage and composition of the migratory birds using that location. Thus, the impacts are likely to be site specific. However, I forecast the following general types of impacts:

Direct impacts include:

(i) Loss of intertidal feeding areas and roosting/resting areas;

(ii) Displacement of bird populations to adjoining wetlands or possibly to nearby agricultural lands with possibility of bird vs farmer conflicts;

(iii) Migratory species, especially those using coastal areas as stopovers during long migrations are especially likely to be sensitive to losses as they may already be stressed/fatigued by their journey and may be less adaptable than resident species. More specialised feeders may also be more greatly affected as they may find it more difficult to find alternative feeding grounds.

Indirect impacts:

(i) Changes to the adjoining physical coastal environment and habitats instigated by the effects of the reclamation e.g. large reclamations in estuaries reduce the tidal prism, slowing tidal currents and potentially leading to enhanced siltation. Outer estuary areas can become increasingly sandy and so alter the nature of remaining intertidal bird feeding grounds;

(ii) The reclaimed area is likely to result in increased disturbance from the human activities associated e.g. port facilities, airports, residential or amenity areas. This could take the form of noise, light or even more frequent intrusion of people into adjoining areas e.g. increase in watersports/recreational boating can be especially disturbing;

(iii) The reclaimed area may result in increased risk of pollution incidents that could affect adjoining areas e.g. oil spills, hazardous chemicals, sewage, eutrophication etc.

(iv) Increased human usage associated with the reclamation could result in greater risk of escapes of alien invasive species that could adversely affect habitats.

In summary, the diverse and potentially far reaching effects of reclamations means that their impacts can be significantly greater then their actual geographical footprint. That is why robust environmental assessments are required to estimate impacts and define requirements for compensatory habitat restoration. 

A final consideration is the cumulative impact of these factors operating at many reclamation sites across the migratory range or path of a species. That is very difficult to account for or compensate for as reclamation schemes are typically assessed and compensated for on a site by site or local region basis.

I've listed a couple of links below, but more specific searches and literature linking migratory birds and coastal habitat changes would appear to be required. 

I wish you success with your research!

https://water.usgs.gov/nwsum/WSP2425/birdhabitat.html

http://www.securecms.com/igarss2008/abstracts/pdfs/1203.pdf

Dear Malcolm Bray

Thanks a lot for your help.

Ning Li

I'm not sure what you mean by coastal reclamation,but my experiences in developing artificial  habitat have provided significant roosting areas for migratory especially and yes - round resident species.