The northern side of the island is renown for its breeding population of Bluethroats, Black and Red Kites, Marsh Harrier, Black Woodpecker (which is difficult to find), huge numbers of Nightingales, good numbers of Golden Orioles and Great Reed Warblers. I spent many days wandering the area and located many excellent species. There used to be large concentrations of Garganey, but during the period I was in Germany these figures crashed dramatically, and so did the number of Red-backed Shrikes. On my last visit in 1995 Little Egret had appeared, and they are probably breeding in the vicinity somewhere. Penduline Tit had not moved in but there were breeding to the south at Lambertheim (along with Purple Heron).
The biggest problem with Kuhkopf in the summer are the mosquitoes, and through bitter experience (150 bites in one hour) I would recommend that people use the strongest insect repellent on the market. Access to the best areas is prohibited, and the path has been altered to keep visitors away from the northern reed beds which hold Bluethroat and Great Reed warbler. There is a small pool near the Stockstadt entrance which used to hold Bluethroat but I don't know if it still does.
The Rhine has also produced Little Ringed Plover, Osprey and Kites - Golden Orioles often fly across the river. On the northern tip of the island where the ox bow meets the Rhine there are some sandbars, and it is here that a few waders appear in both spring and autumn. In winter the fields to the north of Godellau/Erfelden entrance hold vast numbers of Bean Geese - the Rhine also holds some rare sea ducks, and I have seen Eider, Smew, Merganser, Goosander and Goldeneye there.
My old contact in this area was Peter Peterman, and he used to produce an annual paper on this area. Any more information could be sought from him. Alas, I no longer have his address.
Not the most beautiful of cities nor one which would be expected to hold any birds, but there are areas within the city which do hold interesting birds. I used to work an area to the west: take the U Bahn (number 22 I believe) to Heerstrasse and continue along the metalled road towards the motorway, pass under the bridge and follow the path. The bushes hold Serins, Red-backed Shrikes and the usual finches. At the first junction turn right down to a little stream and then continue west along its banks. The trees hold Golden Oriole, Nightingale, Marsh and Grasshopper Warblers. During August/September there is a massive movement of raptors, and I recorded 15 species during my stay. Over 1,000 Buzzard, 200 Red Kites, 80 Marsh harriers pass through this area during these months. I have also recorded Black Stork, Tawny Pipit, Red-footed Falcon, Osprey, Honey Buzzard, Montagu's Harrier, Merlin, Rough-legged Buzzard, Peregrine, and even a Black Woodpecker at this site. It is hardly attractive with a major motorway, an S Bahn and bare sugar beet fields, but the visible migration at the right time of the year is something special.
This southwestern suburb of the city is an area of allotments and sand pits, but there are a few interesting birds here too. Woodlark, Wryneck, Hoopoe, Golden Oriole and Black Kite make this an interesting area for a few hours in spring. Wrynecks breed here in some numbers, as there are still a few orchards, and a pair of Woodlark use the sandy areas for nesting.
This area is reached by following the road from the Geiselweisen stop and going along a small passage to Nidda Zoo. The bushes used to hold Red-backed Shrike but they have probably disappeared by now. The woods hold Grey-headed Woodpecker and vast numbers of Hawfinch and Bramblings in the winter. I have seen large flocks of Crane moving overhead in late October from this site. Marsh Warbler is common, and other warblers are fairly well represented in this area.
The woodland to the south of the city hold all the normal species, but on my return there a couple of years ago I was pleased to see Black Woodpecker - it would seem that they have extended their range in Germany, and this may be part of the infilling - unusual as these woods are at a low elevation. Tree Pipit are common in the summer, and Hawfinch are ever present. The beauty of this area is somewhat marred by the constant noise of planes flying very low over the area on their approach to Frankfurt airport.