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APPENDIX
1: JUVENILE MIGRATIONS
The report 'Toads On Roads, In Car Parks and Down Drains'
was produced in 1998 by Marcus and Susan Phillips. As a result of
this, in early 1999 a toad lift was organised and a subsequent 1999
report produced. This text forms Appendix 1 of the 1999 report and
concentrates on the monitoring and rescue of amphibians produced
from spawn laid during the period February to April 1999.
ABSTRACT
The disruption to froglet and toadlet migration routes caused by
roads and drains can greatly influence the outcome of a successful
spawning. This appendix summarises the findings of a detailed study
on the migration of amphibians produced from spawn laid during the
period February to April 1999.
INTRODUCTION
The spawning site is a balancing pond at 'Saxon Gate'; a
new housing development just off the Al at Biggleswade in Bedfordshire.
Until 1990 the whole area formed part of Kennel Farm and was 'arable
desert' i.e. intensively farmed arable land and allotments inimical
to most wild life. There were, however, ditches with adjoining scrub,
the remains of an old moat and a pond whose area was given on the
map as 0.3 acres (0.12 hectares). The construction of a housing
estate began in 1992 but was slightly delayed when a medieval village
was revealed on the site. In 1993 a circular 'balancing pond'
approximately 50 metres across was dug on the site of (or close
to) the pond to take surface run off. We noticed a few toad tadpoles
there in the spring of 1994. Since this pond is steeply shelved
it was fenced off with metal railings. This did not stop quantities
of refuse being dumped in it. Some shrubs have been planted alongside
which are regularly sprayed with glyphosate ("Roundup").
An indoor swimming pool and car park was built in 1996 to the north
of the pond. Raised flower beds, also sprayed, are a feature of
the car park.
The pond is bounded by roads on the south, east and west which function
as access roads to residential areas, to a new housing development
and to the swimming pool car park. A boundary hedgerow running north
to south has been retained. To the east of this is the new road.
A toad tunnel has been constructed at the southern end of the new
road (Refer to Figure 1). Building is continuing to the north and
a linear wood some 45 metres deep will be planted to the east alongside
the new road.
The new road was laid towards the end of the adult migration in
April. The road was not opened to traffic and thus provided an opportunity
for detailed monitoring of the juvenile migration. The road's
high kerb stones and 26 gulley pot drains provided an ideal
combination for pitfall traps. Laying of the toad tunnel did not
interfere with the juvenile migration.
The main toad lift recorded 2500 amphibians rescued between late
February and May. The metamorph lift commenced in June and finished
in July. Over 14,000 froglets and toadlets were rescued from the
site, 8000 were collected from the drains on the new road. Detailed
records were kept of where and when metamorphs were rescued. These
records have revealed a great deal about juvenile migration away
from the spawning site.
GENERAL OBSERVATIONS
Froglets and toadlets are good climbers up the sides of wet buckets.
We were constantly having to force them to go to the bottom and
start again. Many were seen consistently trying to climb up the
sides of drains.
The juvenile migration commenced with movement of froglets observed
on 6th June. Froglets appeared to wander around the banks of the
pond most of the time, only moving away during and after rainy weather.
Froglet activity peaked after the 11th of June, approximately 3.5
months after the start of the adult migration.
Prior to commencement of the main toadlet migration, signs were
put up in the swimming pool building asking the public to contact
the IWG if large numbers of baby frogs and toads were seen trying
to cross roads.
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