|
|
"It
can be asserted with a fair degree of certainty
that neither the heron nor the spoonbill will ever
again breed in London outside the Zoo."
(Fitter,
1949) |
Download
this Action Plan in full
1. Aims
 |
To
conserve London's grey heron population by protecting
existing and newly established heronries, roosting and
foraging habitat. |
|
To
raise awareness of grey herons, their requirements and
their value as an indicator of healthy rivers and water
bodies. |
2. Introduction
Grey herons (Ardea cinerea) are easily recognised
and appreciated by most Londoners and capture public imagination.
However, despite their characteristic dark wings and black
crest they are often mistakenly known as 'stork' or 'crane'.
Herons are at the top of the food chain in freshwater habitats
and their presence can indicate a healthy freshwater environment.
Huge improvements in the water quality of the River Thames
and its tributaries have provided a plentiful food source
for herons, allowing them to increase and spread. London
is a heron hotspot and in 1985 contributed about 1% of the
United Kingdom population.
3.
Current Status
Grey herons breed colonially, usually at the tops of tall
trees on islands that offer some degree of protection from
disturbance. All London's heronries are in such locations,
with the exception of Lonsdale Road Reservoir where they
nest on tern rafts.
The British Trust for Ornithology (BTO) Heronries Census
provides excellent information on heron numbers, which are
currently at their highest levels. During the last nationwide
census in 1985, London had three heronries containing 114
nests. By 2000, this had gone up to 16 heronries with 302
nests. Heronries are found in the following London Boroughs:
Bexley; Bromley; Hillingdon; Hounslow; Merton; Richmond;
Waltham Forest; Wandsworth and City of Westminster (see
Annex for map and further details). There are also two heronries
(Kempton Park and Stocker's Lake) just outside the Greater
London boundary.
Nationally, the average size of heronries in England is
about 18 nests (Marchant, 2000). The heronry at Walthamstow
Reservoirs is one of the largest in the country, with 110
nests in 2000 · excluding this site, the average in London
is 13. Recently established heronries demonstrate that new
sites can be found in London, though the number of suitable
locations for future heronries is limited. The only recent
instance of a heronry failing to become established was
at Kew Gardens (London Borough of Richmond), where two pairs
nested between 1989 and 1991.
4.
Specific Factors Affecting the Species
4.1 Water Quality
The increase in heron numbers in London can be attributed
to the improvement in water quality and the recent run of
mild winters. The improvement in water quality has led to
higher natural fish populations, augmented in some places
by direct stocking. The continuing commitment to improvements
in water quality is likely to lead to further increases
in fish populations.
4.2 Severe Winters
The Heronries Census shows that severe winters have a major
impact on heron numbers (Marchant et al, 1990). Numbers
can decline sharply in severe winters and may recover to
previous levels within five years. The last severe winter
was in 1985/86.
4.3 Disturbance
and Persecution
Despite their clear adaptation to busy urban environments,
heronries, day roosts and foraging habitat remain vulnerable
to disturbance from recreational and development activity.
The most vulnerable period is while birds are sitting on
eggs and it is often not realised that birds can be incubating
as early as February.
Herons that visit garden ponds may not be welcomed by the
owners. The extent of any persecution in London is unknown
and is most likely to be a problem from individuals keeping
expensive Koi carp. Discarded fishing line is also a threat
to herons and other wildlife.
4.4 Cormorants
The increasing inland cormorant population may become a
threat to herons if they compete for the same nesting sites.
They began nesting at Walthamstow in 1990 and Broadwater
in 1997 and by 2000, there were 240 and 15 nests respectively.
At both sites, the herons and cormorants use different islands
and at the moment there is no conflict.
4.5 Disease
Recently, a number of young from a heronry in Nottinghamshire
have been badly deformed and died in the nest (Blackburn
& Kent, 1999). The cause of these deformities is unknown
and the phenomenon has not been observed in London.
5
Current Action
5.1 Legal status
The Wildlife and Countryside Act (1981, as amended) protects
grey herons from killing and catching, being held in captivity,
and the wilful destruction of their nests. It is possible
to apply for a licence to kill birds where they are proven
to cause serious damage at fisheries.
5.2 Mechanisms targeting the species
These current actions are ongoing.
They need to be supported and continued in addition to the
new action listed under Section 7.
5.2.1 Survey and monitoring
Each year, volunteers count the nests in London's heronries
for the BTO Heronries Census. The grey heron is included
in the BTO/WWT/RSPB/JNCC Wetland Bird Survey (WeBS) and
volunteers make monthly counts at many sites in London (see
Annex).
5.2.2 Advice
The RSPB has produced a free advisory leaflet, 'Herons
and Garden Fish Ponds' that gives advice on deterring herons
from taking fish.
6.
Objectives, Actions and Targets
Most of these actions are
specific to this species. However, there are other, broader
actions that apply generically to a number of habitats and
species. These are located in a separate 'Generic
Action' section
which should be read in conjunction with this document.
There are generic actions for Site Management, Habitat Protection,
Species Protection, Ecological Monitoring, Biological Records,
Communications and Funding.
Please note that the partners
identified in the tables are those that have been involved
in the process of forming the plan. It is not an exclusive
list and new partners are both welcomed and needed. The
leads identified are responsible for co-ordinating the actions
· but are not necessarily implementers.
Objective 1 Maintain the current number of heronries
Target: Between 15 and 20 heronries at the end of 2011
|
Action
|
Target Date
|
Lead
|
Other Partners
|
|
Establish Heron Working Group (HWG)
to develop and share knowledge and information
|
2001
|
GLA
|
BTO, LA, LNHS, LWT,
NT, RP, RSPB, TW, WWT, Syon Park
|
|
Protect trees in all current heronries
where they may be threatened through TPOs
|
2003
|
LTOA
|
GLA, LA
|
|
Produce and disseminate best practice
document for habitat improvements around heronries.
To include information on minimising disturbance and
appropriate habitat management for young
|
2004
|
Working Group
|
GLA
|
Objective 2 Develop and implement an ongoing research and
monitoring programme
Target : Establish monitoring programme by 2001 and assess
importance of day roosts by 2003
|
Action
|
Target Date
|
Lead
|
Other Partners
|
|
Count all heronries annually through
BTO census
|
Ongoing
|
BTO
|
Volunteers
|
|
Extract heron data from monthly WeBS
counts
|
2001
|
WWT
|
Volunteers
|
|
Develop a programme to monitor breeding
success at selected heronries
|
2001
|
BTO
|
Working Group
|
|
Identify established day roosts and
assess their importance
|
2003
|
WWT
|
Working Group, LA,
LNHS, LWT
|
|
Conduct research into the viability
of artificial breeding platforms in current heronries
where nesting sites are threatened
|
2004
|
Working Group
|
LA, NT, RP, TW
|
Objective 3 Generate an awareness of grey herons and their
requirements to the general public, as well as anglers,
site owners/managers and planners
Target: Promote ways of resolving conflict with pond owners
by 2001, hold first Heron Day in 2002
|
Action
|
Target Date
|
Lead
|
Other Partners
|
|
Promote RSPB leaflet on conflict between
herons and garden pond owners through local authorities
using libraries and other outlets
|
2001 & ongoing
|
RSPB
|
LA
|
|
Hold an annual 'Heron Day' at several
accessible sites, where the public can view heronries
when young are in the nest
|
2002
|
Working Group
|
LA, LWT, NT, RP, TW,
WWT
|
Relevant Action Plans
London
Plans
Woodland; Tidal Thames; Canals,
Private Gardens, Grazing Marsh and Floodplain Grassland;
Marshland; Reedbed; Ponds, Lakes and Reservoirs
National Plans
Coastal and Floodplain Grazing
Marsh, Reedbeds, Eutrophic Standing Waters
Key References
Blackburn, A & Kent, J
(1999). Problems at a Heron colony. BTO News Number
224.
Fitter, RSR (1949). London's
Birds. Collins, London.
Gibbons, DW; Reid, JB &
Chapman RA (1993). The New Atlas of Breeding Birds in
Britain and Ireland: 1988-1991. T & AD Poyser, London.
Marchant, JH (2000). Herons
in 1999. BTO News Number 228.
Marchant JH; Hudson R; Carter
SP & Whittington P (1990). Population trends in British
Breeding Birds. BTO.
Abbreviations
|
BTO · British Trust for
Ornithology
GLA · Greater London Authority
JNCC - Joint Nature Conservation Committee
LA - Local Authorities
LNHS · London Natural History Society
LTOA · London Tree Officers Association
LWT · London Wildlife Trust
|
NT - National Trust
RP - Royal Parks
|
Contact
The Lead for this species is
LB Wandsworth
grey heron © Andy Fisher
for Table of Heronries in London
download the full document
Home
|
