I have been looking at the area of gorse, broom, rosemary and other shrubs on the steep south facing slope below the bowling green. This now well established planting, originally suggested by the first Wildlife Park Group over 10 years ago, is becoming too overgrown with Traveller's Joy (Clematis vitalba) and various other 'intruders'. The Wildlife Group are hoping to clear back some of this unwanted growth (contact simonrandolph@hotmail.com for further information).

However, while assessing what clearance might need to be done, I spotted a bumblebee queen ( Bombus lucorum or B. terrestris) flying persistently around a patch of rosemary. After several minutes she flew under the bush and went straight to a small hole in the earth where she then wriggled down into it, apparently trying to excavate some of the soil, so that she could go deeper. I am fairly sure she was searching out and then trying to make a suitable hibernation site for herself. If she has settled in there for the winter, will she survive our pruning and gardening activities in that area? Probably not.

This goes to show how easy it is to have good intentions to 'improve' a piece of habitat for some types of wildlife while almost certainly unwittingly damaging or even destroying it for others! In this particular case, the improvements we were aiming to make were intended to be of benefit to bumblebees! How can one possibly assess whether it is more important to try and protect this area as a hibernation site (potentially for several bumblebee queens) or to clear the rampant Clematis from the gorse and broom, which will encourage more prolific flowering and thus provide much valued sources of nectar for bumblebees, particularly the queens when they emerge from hibernation in the spring? An impossible dilemma. As always, it has to be a compromise decision!

Simon Randolph

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Hawthorn, Blackthorn and biodiversity


Two major aims of the Wildlife Group involve increasing the variety of wildlife in the park and hopefully at the same time, improving the visual attractiveness of the park (both for its human and wildlife users). We hope these linked aspirations will be achieved with the creation of the wildflower meadow area once it has become fully established.

It recently occurred to me that we might successfully pursue this policy in yet another way. The park is at present entirely lacking in two common hedgerow species, the hawthorn and the blackthorn. Together in the spring, they provide an extended and spectacular display of white flowers that are attractive to a variety of bees and other insects for their pollen or nectar. Additionally, in autumn they go on to develop valuable fruits for birds in the form of haws and sloes. These features alone would surely merit their consideration as suitable candidates for inclusion in any further wildlife planting scheme for the park.

Given our central aim of encouraging a wider biodiversity within the park, the recent appearance on the web of ‘The database of British insects and their foodplants’ looks likely to be a very useful resource in providing information that can guide us in this aim. Here for the first time, a huge number of scientific publications have been searched to compile a detailed picture of many herbivorous insects and their associated foodplants. This list does not at present include those insects that use the plants for pollen or nectar sources. Thus if we type in a request for all the insect species that are known to use the European Black Pine (of which we have 35 specimens in the park) as a food plant, the database comes up with a list of 9 insect species. The Small Leafed Lime (27 trees) has 37 insect species associated with it as a foodplant. For hawthorn, the corresponding number of insect species that have a feeding relationship with this plant is a remarkable 196. For blackthorn this figure increases to a staggering 256 insect species including up to 170 species of moth. We can surely use this fascinating and invaluable information about these latter two plant species to further support a case for developing the park’s biodiversity through the planting of some hawthorn and blackthorn.

It would of course be utterly unrealistic to expect many or perhaps even most of these insect species to find their way to our urban park and establish themselves successfully as residents on any hawthorn and blackthorn that was planted. But the figures do give hope that potentially, if these two common and attractive plant species were growing in the park, they may come to harbour and feed a significantly wider range of insect species than presently occur.
!0 small specimens of
hawthorns and 10 of
blackthorns have now been planted in the park. Let's hope the subsequent dry weather we have had in April won't prevent these young trees from establishing themselves as part of the diversity of plant life in the park. Today,
April 23rd was a warm and sunny day and several days of similar weather have begun to have their effect on the insect life of the park. At least 3
Large Red Damselflies were basking on foliage by the pond (see main photo section). Several
Speckled Wood butterflies were flitting about. There was also a
Hawthorn shieldbug (see main photo section). Let's hope the hawthorns we planted will attract and support increasing numbers of this strikingly hansome insect. There was also a beautifully marked hoverfly,
Helophilus pendulus on a dandelion by the edge of the pond. The photo below shows this very distinctive insect but it was taken in my garden, not in the park!

An actual St Andrews Park Helophilus pendulus individual can now be seen in the photos section!
March 5th '09. Today, a cold but sunny one, I saw several bumblebee queens flying in the park. Perhaps one of these was the queen I saw constructing a hibernation site in the park amongst the rosemary, back in September of last year, though this may be wishful thinking as it is thought that the mortality rate of overwintering queens may be as high as 80%. Emerging from hibernation so early in the year, these were probably Bombus terrestris, the Buff-tailed bumblebee. One individual was busy working the crocus flowers for pollen and nectar (see photo section) but I noticed several visiting the male catkins of the goat willow, along with more numerous honey bees. A lone female Drone fly hoverfly (Eristalis tenax) was also availing herself of the ample pollen and nectar of these willow flowers (see photo section).
March 14th '09. The Mahonia shrubs growing just outside the lower end of the dog-free area are in full flower and their strong scent must surely be an olfactory advertisement aimed at inducing bees into the flowers to effect cross pollination. Both honey bee workers and Buff-tailed bumblebee queens (Bombus terrestris) were visiting the flowers, busily availing themselves of this early spring offering of pollen and nectar (see photos section).

British bumblebees have been suffering badly over the last three or four decades, populations of many species reduced to critically low levels in the countryside by the ravages of intensive farming which have destroyed over 90% of flower-rich unimproved grasslands. This habitat had traditionally provided a vital source of both food and nest sites for many bumblebee species. Of the 25 British species, only 6 are considered to be still 'safe', i.e. common and widespread. At present, it is almost certain that the continuing success of these species (like Bombus terrestris) is largely dependent on the availability of the rich diversity of flowers in urban parks and gardens. Let's hope that with the establishing of our wildflower meadow in the park, we will be contributing a small but perhaps critical additional resource for the survival of our local bumblebees. The reasons for the decline of our bumblebees (in the most up to date and comprehensive book on their natural history) is examined in detail in 'Bumblebees' by Ted Benton. This excellent book is published by Collins in their New Naturalist series.
A male Sparrowhawk drifted over the park at lunchtime, mobbed by a Carrion Crow.
The Wildflower Meadow was sown on May 26th 2009. This will take at least 2 years to establish itself because many of the plants are perennials and will not develop their first flowers until their second year of growth. Some species will be more successful than others and some may not be able to successfully compete with the most aggressive species. However, listed below is the full list of species that should appear over the next two years:

List of species sown for the wild flower meadow:


Birds Foot Trefoil Lotus corniculatus
Black or Common Knapweed Centaurea nigra
Common Sorrel Rumex acetosa
Cowslip Primula veris
Field Scabious Knautia arvensis
Hoary Plantain Plantago media
Ribwort Plantain Plantago lanceolata
Lady’s Bedstraw Galium verum
Selfheal Prunella vulgaris
Yellow Rattle Rhinanthus minor
Ox-eye Daisy Leucanthemum vulgare
Meadow Buttercup Ranunculus acris
Wild Carrot Daucus carota
Yarrow Achillea millefolium
Kidney Vetch Anthyllis vulneraria
Meadow Cranesbill Geranium pratense
Ragged Robin Lychnis flos-cuculi
Black Medick Medicago lupulina
Red Campion Silene dioica
Meadowsweet Filipendula ulmaria
Catsear Hypochaeris radicata


Grasses

Crested Dogstail Cynosurus cristatus
Slender Creeping Red Fescue Festuca rubra
Common Bent Agrostis capillaris
Smaller Catstail Phleum bertolonii
Tall Fescue Festuca arundinacea
I'm delighted to report that this morning I observed a parent Mistle Thrush feeding a juvenile bird in the park, confirming the long-held suspicion among Jo, Simon and I that this species may be breeding. These birds seem to have decreased locally in recent years so it's good to know they breed in our park!
Excellent news! Well spotted, Des. Do you know where it was actually nesting or the kind of site it might most likely have chosen?
It might have been in or near the Ceder (tree 62?) - apparently they nest in both conifers and broad-leaved trees. As they are early nesters this could have been a second or even third brood!

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