Pluralising 'Red Kite'

Is the following grammatically correct?

An area frequented by red kite and skylarks

It would appear to be incorrect as red kite should be pluralised to red kites, however this sounds wrong to my ear.

Is this a grey-area? Or is it definitely incorrect?

Another example usage:

There were sitings of red kite.

Solution 1:

There are animals, like moose and fish, where the plural noun in English is identical to the singular one, and perhaps "kite" sounds like it should belong in that category to your ear, but every source I've seen pluralizes kite as kites.

Solution 2:

Consider...

Greenfinch and red kite are birds belonging to the finch and kite families respectively

Red kite are birds of prey that like to collect things with which to decorate their nests

Personally I don't see anything particularly unusual about such usages in a "species identification" context. We can't do this with all "living creature" identifiers (no-one ever says Cow are important to dairy farmers), but for some of them (sheep, fish, moose, squid) "everybody knows" these words can be both singular and plural. To me, (living) kite can certainly fall into that category.