FACTSHEET NUMBER 7

                                                     FREQUENTLY ASKED QUESTIONS

What are waders?
‘Waders’ is a collective name for the group of birds that can be seen ‘wading’ on the shoreline,
searching for food such as small insects. They include lapwing, oystercatcher, ringed plover,
dunlin, snipe and redshank.
Is Uist special for waders?
Yes. The Uists provide some of the best sites in            How do you know hedgehogs are eating wader
Europe for these birds. In recognition of this, two         eggs?
areas, covering more than 10 000 hectares, have been        A five-year programme of research was started by the
recognised by the European designation - Special            RSPB in 1996 to investigate the cause of the declines.
Protection Areas (SPA), and 13 sites as Sites of Special    Hundreds of nests were located and monitored. The
Scientific Interest (SSSI), a national designation.         researchers were able to tell whether nests had hatched
                                                            successfully or not, and the study found that hedgehogs
Has the size of the nesting population of waders            were responsible for most of the nest failures by eating
changed in the Uist?                                        their eggs. Hedgehogs leave very clear signs when they
Yes. In the mid 1980’s, detailed surveys estimated the      come across a nest and eat the eggs.
wader population to be at least 17,000 breeding pairs.
In 1995, they were counted again and a huge drop was        Has anyone actually seen hedgehogs eat wader
recorded. The most recent survey carried out in 2000        eggs?
revealed the full extent of the declines. In South Uist     Yes. Radio-tracked hedgehogs were followed and
and Benbecula, snipe, dunlin and ringed plover have         observed eating eggs. They have also been filmed and
declined by 60%; redshank by 40% and lapwing by             photographed.
30%. By contrast, in North Uist the estimated numbers
of three of these species (oystercatcher, lapwing and
redshank) increased; dunlin declined by 30% and
ringed plover by 50%.

Why have waders declined?
There is clear evidence to show that high levels of egg
predation caused by hedgehogs is causing the decline.       Can the waders not lay more eggs?
                                                            Even though waders can lay a replacement clutch, a
Although there may be some other factors involved, the
                                                            high proportion of these are also eaten and, at the end
north-south differences reflect the known distribution
                                                            of the year, not enough chicks survive to maintain the
of hedgehogs, i.e. they are absent from northern sites
                                                            population. For some species in South Uist and
but abundant on southern sites.
                                                            Benbecula, less than one pair in five successfully rear
                                                            young in a year.
But some birds declined in North Uist?
True, but for dunlin this was about half as severe as it
was in the South. Nevertheless, the reason for their        What else do hedgehogs eat?
                                                            They eat a wide range of food, mainly invertebrates,
decline in North Uist is not clear. The fall in ringed
                                                            including earthworms, beetles and snails and also
plover numbers is obviously not a hedgehog effect. It
                                                            carrion. Bird eggs form a very small proportion of
is, however, the only wader species which may nest on
                                                            their diet.
a different island each year. This may partly explain
why they have declined throughout the Uists.
                                                            FACTSHEET NUMBER 7

                                                      FREQUENTLY ASKED QUESTIONS

How many hedgehogs are there in the Uists?
The estimate is 5,000 adults, and these will give birth
to around 10,000 young each year. Litters typically          however, unclear as there is no evidence of a
contain three to five young, and some females produce        significant change in gull numbers.
two litters in a season.
                                                             Are mink a problem for Uist waders?
How did hedgehogs get to Uist?                               Mink are non-native mammals from North America,
We know of four hedgehogs brought to South Uist in           which have also been introduced to the Western Isles
1974, a further 3 in 1975. It was thought that they          by humans. However, they are thought to have only
would help to control garden pests (slugs and snails).       reached the Uists around 1999 and their numbers are
Although they are native to the UK mainland, they            low (< 100). Between 1999 and 2001 the Uist Mink
were never found naturally in the Western Isles or the       Group have controlled their numbers and now a major
other island groups around Scotland.                         project is attempting eradication. So far, mink have
                                                             been found mostly on the east coast away from the
                                                             main wader breeding grounds, but they are known to
                                                             be a problem for other native wildlife (terns, gulls and
                                                             waterfowl) and other interests (fisheries, poultry and

D. Jackson

Where are the hedgehogs on Uist?                             To date there is no evidence that they are having a
They are widespread throughout South Uist and                negative impact on Uist waders. For five years from
Benbecula and are spreading northwards through North         October 2001, work by the Hebridean Mink Project
Uist. Currently (2002) they are known to be present in       will attempt to stop any further spread and reduce the
small numbers in Carinish and Locheport, but so far          number of mink from the Uists.
there are very few sightings elsewhere in North Uist.
                                                             Aren’t there any laws against releasing animals?
Are there hedgehogs elsewhere in the Western                 Under current legislation, there are no laws to prevent
Isles?                                                       hedgehogs being released as they are native to the UK.
Lewis and Harris also have introduced hedgehogs, but         There are, however, laws prohibiting the release of
they do not have the high numbers of breeding waders         species, which are not native to the UK, such as mink.
that the Uists support. Waders and hedgehogs have not        The Scottish Executive has said that it is committed to
been studied in Lewis and Harris, and so it is not           strengthening current nature conservation laws and will
known whether they are posing a problem.                     introduce legislative proposals by March 2003.

Are there any other predators which eat wader                Do Uist hedgehogs have any natural predators?
eggs?                                                        To all intents and purposes no, however, very
Yes. Common gulls are also known to take some                occasionally large raptors may tackle a hedgehog. On
wader eggs, but they are native to the Uists. For most       the mainland, badgers and foxes will kill and eat them.
wader species the available evidence shows that egg          Collision with vehicles is one of the most significant
losses to gulls are at a similar level now to what it was    non-natural causes of death. In the Uists, relatively
in the 1980s. However, ringed plover egg loss to             few hedgehogs die in this way due to the very light
common gulls may have increased. This may have               traffic.
contributed to their decline. The reasons for this are,
                                                          FACTSHEET NUMBER 7

                                                    FREQUENTLY ASKED QUESTIONS

What is the future for Uist waders?                        What will you do once hedgehogs have been
If no conservation action is taken wader numbers will      captured?
remain severely depressed in South Uist and                There are several options, including:
Benbecula, and some may even disappear from certain            1. Translocation of hedgehogs to mainland
areas. On North Uist, as hedgehogs spread northwards                Britain.
into the remaining hedgehog-free areas which still             2. Humane lethal control.
support large wader populations, numbers are likely to         3. Sterilisation of the population.
decline in a similar fashion to South Uist and
Benbecula.                                                 Is translocation feasible?
                                                           The Project commissioned a desk-based study to
                                                           investigate this. Although this study found that in
                                                           principle translocation appears to be possible it also
                                                           raised significant welfare concerns both for the
                                                           hedgehogs being translocated and the mainland
                                                           hedgehog populations.

So, how can Uist Waders be saved?
After many years of research, the only viable option is
to reduce levels of egg losses by reducing the hedgehog
population. To achieve this hedgehogs have to be

Surely, it must be possible to keep hedgehogs out
from key areas?
Although one small area is being protected by
hedgehog-proof fencing, this approach can only protect
a tiny percentage of the total Uist wader population,
which is spread over 200 km2.

Why do fences not work?
There are very few places in Uist suitable for special
fencing, because hedgehogs easily find gaps and can        Does that mean humane lethal control of hedgehogs
get through. Hedgehogs can also swim. Experience           is the only way to safeguard Uist Waders?
from the islands shows that standard rabbit-proof          The Uist Wader Project will only consider lethal
fences are constantly breached on dry machair habitats,    humane control when viable non-lethal solutions have
by rabbits burrowing underneath so are unable to           been ruled out.
exclude hedgehogs. Nevertheless, there may be a role
for fencing to slow down their spread in North Uist.
                                                                                         Is it possible to use
Okay, so hedgehogs need to be caught, how is this                                        contraceptives         to
done?                                                                                    reduce the population?
Several methods of catching hedgehogs have been                                          This is also being looked
tested including searching with spot lamps at night,                                     into, but there is
live trapping with baited cage traps and locating them                                   currently no chemical
with sniffer dogs. By marking hedgehogs, living in a       available for use on hedgehogs. Most mammal
defined area it is possible to work out what percentage    contraceptives work for only a short time, perhaps one
of hedgehogs can be located using the different            season. Therefore, treatment would be needed every
methods. So far, spot-lamping in May has proved to be      year. Expert opinion suggests that this technology will
by far the most effective method with up to 70% of the     not be available for many years. Any product would
hedgehogs located in a single search visit.                have to be tested to ensure that it posed no risks to
                                                           other wildlife, livestock, pets or people. Discussions
                                                           with experts are ongoing.
                                                            FACTSHEET NUMBER 7

                                                      FREQUENTLY ASKED QUESTIONS

Are the Uist wader sites protected by the law?               Are there any relevant guidelines about catching
Yes, there are both national and international laws          and moving pregnant hedgehogs?
under which breeding waders sites on the Uists are           There are no specific regulations in relation to the
protected:                                                   collection, transit or release of hedgehogs that are
                                                             carrying or nursing litters. However, the Home Office
European Legislation                                         have a Code of Practice for the Housing and Care of
Under the EC Birds Directive, Member States are              Animals used in Scientific Procedures. This states that
required to take special measures to conserve the            small mammals should not be transported in the last
habitats of rare bird species and of regularly occurring     fifth of pregnancy. For hedgehogs, this would be after
migratory birds. In particular, each Member State is         day 25. The SSPCA recommend that animals should
required to classify the most suitable areas of such         not be transported in the last third or pregnancy. For
habitats as Special Protection Areas. Two sites on the       hedgehogs this would be after day 22.
Uists (North Uist Machair & Islands and South Uist
Machair and Lochs) have been classified as Special           What do we do if we see a hedgehog?
Protection Areas, covering over 10 000 hectares.             If you see a hedgehog in North Uist (except Carinish) ,
                                                             or on the Islands of Baleshare or Berneray it is vital
Under the terms of the Directive, the UK Government          that you let us know as soon as possible, whether it is
is required to maintain these sites in a “favourable         dead or alive. There are currently no hedgehogs in
conservation status”. Declines in the population of          Eriskay either, but they now have access by the new
wader numbers are not compatible with this. Failure to       causeway. Nor have hedgehogs reached Barra and
comply with the Birds Directive may result in the UK         Vatersay.
Government facing legal proceedings.
                                                             Who is involved in the Project?
UK Legislation                                               The Project is steered by a Management Group
The Wildlife and Countrysde Act 1981 allows areas of         comprising Scottish Natural Heritage, RSPB Scotland
special wildlife interest to be given protection by          and the Scottish Executive. The research and survey
designating them as Sites of Special Scientific Interest.    work on the waders and hedgehogs is co-ordinated by
Thirteen sites on Uist have been notified, fully or          RSPB Scotland’s Research Department. A Local
partly, because of important populations of nesting          Liaison Group, which includes representatives from
waders.                                                      local estates, the crofting community and the Western
                                                             Isles Council has also been established.

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