Mediterranean Garden Society
Wildlife gardening in a mediterranean climate
The photograph at the top of this page shows summer-dormant Ptilostemon chamaepeuce, a thistle-like Greek native plant growing at MGS Sparoza garden (Photo Rosey Boehm)
As Melissa Hamilton reminds us that we gardeners have a unique opportunity to assist our native wildlife to feed and breed. By planting a variety of native plants, avoiding pesticides, providing a little water and leaving undisturbed corners we can easily create a wildlife haven. In the articles below, reprinted from the MGS journal, you will find inspiration and practical advice to achieve that goal.
Going Native - Garden Design for Wildlife
by Melissa Hamilton, reprinted from TMG No. 85, July 2016
Melissa makes suggestions for designing a wildlife-friendly garden.
by Melissa Hamilton, reprinted from TMG No. 83, January 2016
Melissa reminds us how to offer sanctuary to wild creatures and why we should want to.
For additional reports and articles on this subject please check out the (non-responsive) MGS Archive.
Making native plants the cornerstone of your garden protects our environment, and at a regional level can rebuild corridors of native vegetation in urban and rural landscapes. Moreover, as well as having an emphasis on native plants in your garden, there are many other elements that you can try incorporating into your garden design that will assist local wildlife.
The story of storeys
When planning your garden, try to incorporate as many storeys as you can: the upper storey (or canopy), mid-storey and understorey all have important roles for birds and other wildlife. The upper canopy, the taller trees, is where many birds feed, and it is also used as a vantage point to check for predators. The mid-storey is usually made up of climbing plants, which offer a safe bridge from the upper canopy to the understorey, and larger shrubs. Depending on the plants chosen for the mid-level, this can also provide food for insectivorous and nectar-feeding birds.
The understorey is very important for the ground-feeding birds. If you have a tree surrounded by lawn, then birds (such as blackbirds and robins) will be feeding in the open with a greater distance to cover to get back to safety. A good understorey will incorporate native plants that provide both cover and food for birds that feed on or near the ground. Plant diversity, in terms of both species and height, will encourage a range of birds in your garden. Where there are only one or two dominant plant species you may similarly notice that one or two types of birds dominate your garden. For example in Australia the popularity of exotic flowering plants and native hybrids with larger flowers has been very beneficial to the Noisy Miner (Manorina melanocephala) but detrimental to the smaller honeyeaters which have been pushed out of many urban gardens. A range of flower sizes and types should mean that there are different plants available to different birds.
It’s not just dead wood
If you look carefully at any large dead tree, or large trees with dead branches, then you will see nature’s apartment blocks. If there is no danger in leaving dead trees or branches in place, then consider waiting for nature to take its course. Dead wood is a source of insects for birds and other animals, as well as providing important nesting places for woodpeckers, owls and other birds such as the Eurasian wryneck (Jynx torquata), which nested one year in a hole in one of our large oak trees. Even once they have fallen, dead branches continue to provide cover, basking sites or foraging sites for lizards, birds and small mammals. Don’t remove fallen logs if you don’t need to, or if they fall in an inconvenient place simply move them to another spot in the garden.
As part of waterwise gardening Olivier Filippi and others within the MGS have been promoting the use of lawn alternatives. As well as the benefits for a dry garden, there are very good reasons to use lawn alternatives for local wildlife. Lawns provide little in the way of food for birds and pollinators. Wildlife-friendly alternatives on the other hand, like native grasses or groundcover plants such as Thymus roegneri, will support a wide range of bees, butterflies and other pollinators. Traditional lawns also require more chemicals than lawn alternatives. Many fertilisers, herbicides and pesticides used on lawns have been linked to bird mortality. In 1998 David Pimental, a professor at Cornell University, estimated that about 72 million birds were killed in the United States each year because of direct exposure to pesticides. These numbers did not include the deaths of nestlings fed pesticide-contaminated insects and earthworms.
When bird-watching along remote rivers we have often seen large groups of butterflies gathered at the water’s edge, and wondered why. This activity is called “puddling” and principally occurs around mud or where soil is saturated. The butterflies are gathering sodium and other minerals from the wet soil using their probosces. This sodium is essential for successful breeding as butterflies use a lot of sodium in producing and laying their eggs. So why not try and attract them to your garden with some strategically placed mud puddles?
Standing water should be avoided because of mosquitoes, so try to plan puddles that can be re-moistened as necessary but which have sufficient drainage. Putting mud in a shallow tray or bowl, or in raised wooden boxes, should do the trick, and could create an interesting feature in your garden. Certainly if you succeed in getting it covered with butterflies it will become quite a talking point… Your mud can be either dirt- or sand-based, but try to use soil with a high mineral content and little organic material. You can even make a sodium solution with sea salt and water to add to the mud for a richer offering. Other wildlife will also appreciate access to a good mud source. Some birds, like house martins (Delichon urbicum) and barn swallows (Hirundo rustica), use mud when building their nests. Many types of bees also build hives or fill breeding tubes with mud. As with feeders and water, make sure your mud puddles are protected from predators and ensure that the soil and water are free from chemicals such as garden herbicides and pesticides.
Each year in our garden we see a female mammoth wasp (Megascolia maculata flavifrons), the largest in Europe measuring up to 6 cm. They are solitary wasps, are not dangerous and do not build hives. Instead they burrow into the earth and nest underground. For these wasps and many solitary bees it helps if you leave patches of bare earth (perhaps in the midst of shrubbery), particularly if you have south-facing slopes with well-drained and sandy soils. The warmth on south-facing slopes helps on cold spring mornings and soil that isn’t too compacted makes for easier tunnelling. Solitary bees and wasps are fantastic pollinators in your garden: research in Europe found that some species had to visit over 2,000 flowers in order to gather enough pollen to feed one larva.
Do you dread having to rake up all those leaves in autumn? Fallen leaves are a vibrant part of a healthy garden ecosystem. Whenever you rake or move leaves you reveal a hidden world, full of fungi, insects and other invertebrates. As such, they are an important foraging space for birds, lizards, small mammals and carnivorous insects. Some butterflies and insects lay their eggs in leaf litter, using it as a nursery. If you remove these leaves you may be depriving your garden of next year’s butterflies and moths. Of course most gardens will have spaces which you need to clear of leaves. However, rather than removing them completely consider using them as layers in your compost pile or as mulch around large trees or shrubs and garden beds. Leaves from local trees are a healthier mulch alternative than imported or non-native mulch which can harbour foreign bacteria.
Rock walls and piles
Hard landscaping using dry-stone walls and rock piles provides a very popular habitat for lizards, birds and insects which use the nooks and crannies between rocks to hide, nest or over-winter. Think about making space for larger animals, like toads, by digging out a shallow depression before making your rock pile.
When choosing your plants give consideration to providing a selection of plants for different kinds of wildlife. You should aim to cover these principal food types:
A strategically positioned water feature allows small birds to drink and bathe safe from predators. A fountain or other dripping sound will alert passing birds to the presence of water. To bathe, birds need a shallow area less than 5cm deep. In our bird bath we use large flat rocks to create different depths. We have also found that European toads (Bufo bufo) like to use our ponds to cool off in the heat of summer, their presence usually given away either by a loud plop or by a pair of eyes peeking out from under the water-lily leaves. It took a while for the penny to drop on this one, and a very confused toad was initially “saved” a few times before the humans caught on. In the dry summer months of a mediterranean climate it is very important to provide water for local wildlife. It will often save them a longer and more hazardous journey through open land to lake edges, rivers and canals, which may often be affected by run-off from fertilisers and pesticides.
Cuttings or brush piles
Wrens, robins and other small birds need cover for protection and as a source of insects, and a “brush pile” is perfect for this. Other small mammals and insects will also rapidly take up occupation in a brush pile. When making your brush pile remember that thorny branches are especially good at providing safe cover. And a top layer of evergreen branches will provide good cover and habitat through the winter. If a brush pile seems too untidy for your garden, you could instead stack logs in a pyramid and plant a climbing vine to grow over it. Choosing a native climber which is a butterfly host plant would increase the occupation of your new wildlife home.
Nesting boxes and homes
There are so many homes for wildlife that you can incorporate into your garden. All of these can be purchased online, and many of them you can make yourself. There are nesting boxes for birds and bats, houses for hedgehogs, ladybird and insect boxes and frog and toad homes. Many birds will use barns, open garages or sheds for roosting and nesting, particularly barn owls (Tyto alba) and little owls (Athene noctua). It can all get really exciting if you get further up the food chain. We now have quite a range of buzzards, falcons and even snake eagles (Circaetus gallicus)that keep an eye on our little patch. Hopefully there is at least one of these ideas that you can test in your garden. This year I am going to experiment with some mud puddles. Surrounded by native plants of course.
“Certain gardens are described as retreats when they are really attacks”
Ian Hamilton Finlay
Christopher Lloyd said that gardening “keeps us in touch with the earth, the seasons, and with that complex of interrelated forces both animate and inanimate which we call nature”. And gardeners can, through their planning and gardening methods, make important contributions to their natural environment and, consequently, the health of local wildlife.
Increased urbanisation and agricultural intensification are major factors in a vast decline the populations of birds, bats and insects across the developed world. The vast majority of the declines in numbers are due to habitat loss or, more bluntly, starvation. While there is little that gardeners can do about the latter, we can all take decisions about our gardens that will help native birds, animals, insects and reptiles.
So here then is a call to arms: make your garden a retreat, to be shared generously with local wildlife. Include as many native plants as you can in your garden, and allow native wildlife to feed on “weeds” (wild flowers) and “pests” (prey) rather than eliminating them with herbicides and pesticides. After all, a “pest-free” garden in reality means a food desert to native birds, insects and animals.
Why are native plants so important? Because gardening with native plants increases local biodiversity, according to Doug Tallamy in his book Bringing Nature Home: How You Can Sustain Wildlife with Native Plants (Timber Press, 2009). He makes the point that “if you landscape only with non-natives you undermine the food web” and that “every time we plant an introduced plant, we are reducing the local insect population and thus depriving birds and other wildlife of the food they need to survive and reproduce”.
Increasingly scientists are finding that the abundance of non-native (i.e. exotic) flora in urban landscapes is creating complex problems for foraging birds. Birds use more energy when nesting due to the larger distances to be covered between islands of native vegetation and this has a strong influence on breeding success. An interesting study conducted in the Cambridge University Botanic Garden in the United Kingdom found that female great tits in this, largely exotic, parkland expended 64% more energy per nestling than birds in native woodland. The authors found that exotic plant species typically support low abundances of the arthropod prey (such as arboreal caterpillars) favoured by native birds.
It is predicted that the bird species most likely to suffer declines as a result of growing urbanisation are the small insectivores such as warblers and parids (parids include tits in Europe and chickadees in North America). Even nectar-feeders such as hummingbirds and honeyeaters convert to an insect diet to feed their young, and revert to nectar once the young have fledged. Insects have spent millions of years evolving alongside their native hosts and in many cases are unlikely or unable to colonise an introduced species. Indeed many species of butterflies have particular plants, and in some cases only a single species, that act as their larval host plant. In the past, part of the attraction of exotic plants for gardeners was that they were “pest-free”. However, when you consider the part your garden can play in the local environment, planting natives not only provides more food in terms of insects and pollen but will also guard against the risk of invasive non-native plants and the foreign insects and the diseases they may harbour.
The common house sparrow, well known to anyone living in Europe, illustrates the impact that a change from native vegetation to exotics may have. In the United Kingdom the once common sparrow has declined by 68% since 1977, and has almost vanished from central London. A study run by the RSPB (Royal Society for the Protection of Birds) suggested that the decline was partly due to the popularity of non-native ornamental plants such as Cupressus leylandii. A lack of deciduous native shrubs and trees means there are not enough insects during the breeding season for the birds to feed their chicks.
The planting of native plants is the best step you can take to assist native wildlife, as even supplementary feeding through bird feeders cannot provide all of the natural proteins and vitamins that adult and young birds need. However, in addition there are a number of other steps that interested gardeners can take, including:
The websites of the RSPB in Britain, the Cornell Lab of Ornithology in the United States and BirdLife Australia provide a wealth of information on attracting birds to your garden, feeding them and even making your own nest boxes and feeders. Alternatively you can buy boxes, feeders and food from the RSPB or similar bird societies, such as LIPU in Italy. The websites also detail how to keep your feeders and bird baths healthy for birds. The internet is full of tips for creating something even better than the basic cuttings pile described above, for those who want to attract even more birds (try searching under “brush pile”).
If you garden in the United States you can also consider joining “Yardmap”, a citizen-science project being run by Cornell University. The project promotes bird-friendly landscaping and has already resulted in 25,000 acres of habitat in backyards, parks and urban areas in the United States. For those in the United Kingdom more than 170,000 people have signed up for the “Homes for Wildlife” initiative being run by the RSPB. And in Australia you can join the Birds in Backyards programme run by BirdLife, which was “developed in response to the loss of small native birds from our parks and gardens, the rapid expansion of our urban landscape and the consequent loss of habitat for native birds”.
If our garden is any example, the results of using native plants can be seen almost immediately. We try to limit ourselves to plants from the Mediterranean Basin, although admittedly there are many plants even in this distribution that are not truly native to our exact location, such as some of the species of Phlomis which we have planted or plants which are more commonly found on the coast. We avoid all “mediterranean-climate” plants from the Americas and Australia. We make an exception of course for plants for use in the kitchen, such as herbs and fruit trees, but the herbs we grow have been cultivated in Italy for many centuries. Overall, however, we estimate that more than half of the plants in our garden are native; if plants from the wider Mediterranean Basin are included that number would be between 80 and 90%.
A wealth of local wildlife uses our garden. The flowering plants have attracted a large variety of insects and a multitude of bees, mainly solitary bees but also honeybees. The various European salvias and lavenders are favourites of both hummingbird hawk-moths (Macroglossum stellatarum) and bees.
We also have the occasional mammoth wasp (Megascolia maculata flavifrons), the largest in Europe with the female reaching up to 6 cm. With her striking double yellow bands on a primarily black body she initially caused quite a stir, until we discovered that these wasps do not use their sting other than for disabling their prey (which, thankfully, is not us).
The increase in insects has also been beneficial for lizards. As well as the common European wall lizard (Podarcis muralis) we now have a family of European green lizards (Lacerta viridis) breeding in our garden. These are about twice the size of the wall lizard, up to 40cm compared to 20cm, of a brilliant green and with a turquoise throat.
Each year we add to the list of butterflies found in our garden, as it increasingly provides their larval host plants. Wild and bronze fennel (Foeniculum vulgare) host the large and beautiful swallowtail (Papilio machaon). After planting Etruscan honeysuckle (Lonicera etrusca) a few years ago we have seen it used by the southern white admiral (Limenitis reducta) for its larvae. The stunning peacock butterfly (Inachis io) is a compelling reason to leave patches of stinging nettle (Urtica dioica) along banks and at the bottom of the garden. On a less positive note we identified a geranium bronze in our garden (Cacyreus marshalli) a number of years ago. Though we have no pelargoniums, these butterflies were introduced on these plants from South Africa to Europe, and are spreading due to the popularity of pelargoniums.
The bees and wasps provide food for the gorgeous European bee-eaters (Merops apiaster) which nest in the sand banks across the road from our garden.
The local deciduous oaks in our garden and on the surrounding hillside provide food and nesting sites for great tits (Parus major), blue tits (Parus caeruleus) and the delightful and highly social long-tailed tits (Aegithalos caudatus)
Shrubs and hedging are used by common nightingales (Luscinia megarhynchos), whose songs we enjoy throughout spring and early summer, as well as blackcaps (Sylvia atricapilla) with their similar but less complex song and Sardinian warblers (Sylvia melanocephala).
We constructed two bat boxes last year, using plans available on the internet. In fact we had happily constructed one and then as we read further through the instructions we discovered that the females and juveniles roost separately from the males, so we launched in to building the second box to ensure we did not create any uncomfortable social situations! We now have at least one resident in the boxes.
While owls are generally more often heard than seen, we have been lucky enough to see a Eurasian scops.
One evening we were surprised by a short-eared owl (Asio flammeus) which landed on the seat of an old bicycle that was standing in the garden.
We are, currently, on the losing side in the “Battle of the Voles” who have eaten the roots of more of our plants than I would like to admit. Our strategy to date has been to cross our fingers and hope that the owls and the non-venomous green whip snakes (Hierophis viridiflavus) that use our shed (literally in fact, when they slough) will enjoy the abundance of food and bring the vole numbers back into balance.
The environment is an enormously complex web of interrelated forces and thus there are rarely going to be black and white answers. There will always be very good reasons for including non-native species in your garden, for example the conservation of rare and endangered species as is valuably, and highly commendably, done by many MGS members. However, where your choice of a non-native plant is because it will look good, be low-maintenance or be pest-free, I would urge you to reconsider and choose instead a native plant. To protect our native environment, and to work to rebuild corridors of native vegetation in both urban and rural landscapes, we should all try to make native plants the cornerstone of our gardens.
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