Members of Thomson Ecology had a busy day carrying out a bird survey on an area of marshland in Greater London last week.
We recorded a buzzard, a sparrowhawk, two kestrels (male and female) and at least two marsh harriers, one of which was foraging over the marsh in a typical
quartering flight. Four raptor species in one morning is a good tally!
Also recorded was a snipe, several singing Cetti’s warblers, a group of at least 20 male and female bearded tits (also known as bearded reedlings), four
stonechats and small flocks of meadow pipits, linnets and reed buntings.
Marsh harrier and Cetti’s warbler have dramatically increased in numbers and expanded their British range in the past 50 years. Marsh harriers were extinct
in the UK in the late 19th century but returned to breed in small numbers in the 1970s. Now, due to habitat management of reedbeds and less persecution,
the breeding population is estimated at more than 350 pairs. Cetti’s warbler first bred in the UK in 1973 and are now found in suitable habitat throughout
the southern half of the country. Bearded tits have a more complicated recent species history in Britain but overall their numbers also increased greatly
in the 20th century. The increases in Cetti’s warbler and bearded tit are probably related to the trend towards warmer winters.
The winter bird survey season will continue until early March. In spring, when the breeding bird survey season begins, sites such as this could prove to
contain an even greater variety of species.
Contact us if you would like to discuss bird surveys on your site.
Image: Vincent Van Zalinge