Wednesday 9 April 2014

Nesting Season


After days of consideration, a pair of cheekadees has decided to move into the house we made for them. 

They are busy gathering moss for the nest from an old pear tree.  At the same time a pair of bushtits is building a nest on the neighbour's fir tree, collecting lichens from the same pear tree, and flying back and forth from one tree to the other almost all day.


A Red-tailed bumblebee queen (Bombus mixtus) was also checking out the birdhouse for a potential nesting site, but the cheekadee chased her away. 


Some bumblebees, like red-tailed (Bombus Mixtus) and orange rumped bumblebee (Bombus Melanopygus) will sometimes nest in birdhouses if there is an old bird nest still inside. 


A Red-tailed bumblebee queen (Bombus mixtus) finding some 
refreshments on a heather before continuing her search for  a home

It's been couple of weeks since warmer temperatures awakened bumblebee queens in Vancouver. After spending the entire winter underground they are busy looking for suitable nest sites. Bumblebee queens do not build their own nests but use abandoned mouse or bird nests, or even insulation in the house attics. It is important that at this crucial time they have a good supply of nectar and pollen. In my garden they will sometimes visit heathers and flowering quince, but their real favourites are red-flowering currant, oval-leaf blueberry (a native blueberry that flowers extra early) and salmonberry. Read more about the bumblebee's life cycle  in this guide.

A Yellow-faced bumblebee queen (Bombus vosnesenski) on an Oval-leaf blueberry (Vaccinium ovalifolium)
Red-flowering currant (Ribes sanguineum)
A Yellow-fronted bumblebee queen (Bombus flavifrons) on red-flowering currant


Friday 7 March 2014

Beyond Bird Feeders


American Goldfinch
I've come around a new research paper from international team of scientists who over 3 years collected lists of plants and birds from 54 cities from 10 countries around the world. 
Black-headed Grosbeak
What they've found is that urbanization has caused cities to lose large numbers of native plants and birds, but still retain a number of native species thanks to existing green spaces. In the conclusion the authors encourage restoration of native plant species and inclusion of biodiversity-friendly habitats in the design of the cities. It is a common sense, really. The current exhibition Rewilding Vancouver at the Museum of Vancouver explores a similar theme.

I think that we, gardeners in cities and suburbia can also help restore local biodiversity by changing the way we garden and the kind of plants we include in our gardens. As Sara Stein points out in her book Noah's Garden "…we have left our land too retarded to take care of itself, much less to be of any help to us. This is not someone else’s problem. We — you and I and everyone who has a yard of any size — owns a big chunk of this country. Suburban development has wrought habitat destruction on a grand scale. As these tracts expand, they increasingly squeeze the remaining natural ecosystems, fragment them, and sever corridors by which plants and animals might refill the voids we have created. To reverse this process — to reconnect as many plant and animal species as we can to rebuild intelligent suburban ecosystems — requires a new kind of garden, new techniques of gardening, and, I emphasize, a new kind of gardener."

Evening Grosbeak
In relation to the above mentioned study, I wanted to talk about terrestrial birds that live in, or migrate through, the coastal region of the Pacific Northwest, and, specially, my North Vancouver garden. I keep one bird feeder in my backyard since my garden, as it is now, does not provide enough food for birds, especially during the winter. While bird feeders may help some birds through the winter, at the same time they cause unnatural crowding, making it easier for birds to pass around diseases. Also, they favour birds that are better adopted to using feeders over ground feeding birds or birds that are not big seed eaters. 

  Pine Siskins are susceptible to salmonela bacteria that is easily transmitted
 as birds crowd at bird feeders

Providing habitat and natural food is a better way to go than just hanging out feeders. If you want to plant a bush, plant a berry producing one. Plant seed producing perennials and grasses and leave them uncut till spring.

Dark-eyed Juncos are primarily seed-eaters, but during the breeding season
 they also eat insects including beetles, moths, butterflies, caterpillars, 
ants, wasps, and flies.


House Finch is one the rare bird vegetarians, eating almost exclusively seeds and berries.


Do not rake out leaves from garden beds, under bushes or trees. Ground feeding birds like Fox Sparrows , Song Sparrows, American Robins, Varied Thrushes and Spotted Towhee forage on leaf litter in search for slugs, snails, worms, millipedes, centipedes, spiders, beetles and other invertebrates. Apart from providing variety of food for birds, leaves, twigs and pieces of bark that have fallen to the ground also serve as nesting material, while nourishing and keeping the soil moist during summer. So, instead of cleaning up your garden in the fall, sit back and enjoy watching the birds feast on nature's food.

Spotted Towhee is one the birds that spends most of the day scratching around
 in the leaf litter while searching for food.
American Robins eat large numbers of both invertebrates and fruit.
Every year Varied Thrushes come to spend the winter in my garden, 
feeding on berries and creatures that live in leaf litter.

Trees are important part of bird's habitat. Trees and bushes provide larger quantities and bigger variety of food compared to perennials or annuals, in addition to providing shelter and nesting sites.

Downy Woodpecker  eats mainly insects and beetle larvae that live 
inside wood or tree bark as well as ants and caterpillars
Northern Flicker also forages on trees for insects, but often gathers ants and beetles
 from the ground.


In short, if you love birds, you must love insects, and invite them into your yard. Don't use pesticides. Pesticides damage life on so many levels, from your backyard to the ocean, from the basic trophic level to the top. For instance, aphids. Leave them be. They are food many predatory insects and birds. Chickadees, bushtits, warblers and kinglets will spend their summer eating aphids and other insects off your plants and trees. Insects will rarely go out of control and seriously hurt the plant if you let the nature take care of it. I've tried it, and it works! And birds are loving it too.


Orange-crowned Warbler flits through branches searching blossoms 
and leaf buds for food. It feeds exclusively on insects and spiders. 
are other cute birds that drop by in search for insects.



Everybody knows that hummingbirds feed on nectar of flowers, but not many know that they get protein and fat from eating insects, and they rear their babies mostly on insects. Anna's Hummingbird is a year-round resident of Vancouver region, while Rufous Hummingbird overwinters in Mexico and every spring migrates to Pacific Northwest for breading.


Rufous Hummingbird

Native plants are important for our native birds. Apart from providing seeds and fruit for adult birds to eat, native plants provide essential food for baby birds, insects and caterpillars. In fact, 96% of terrestrial birds rear their young on insects and most of them on caterpillars. 

This Black-capped Chickadee was gathering moss
 from the tree for her nest.
In summer Red-breasted Nuthatches eat mainly
insects, beetles, caterpillars, spiders, ants, and
earwigs, and they raise their nestlings on these 
foods.
For instance, chickadee needs six to nine thousand caterpillars to grow one clutch of babies (Doug Tallamy counted the caterpillars). However, most of the caterpillars are picky when it comes to which plants they can eat in order to grow, since they've evolved to digest only certain plant's chemicals. Think monarch butterflies (they don't live around here, but almost everybody has heard of them), whose caterpillars can feed only on milkweed. The decline they are experiencing is partly due to the vast land along their migration route being planted with GMO corn and soy, whose herbicide resistance enabled farmers to eradicate all weeds, including milkweeds from their land (read more here). 
The same is true for our local butterflies and moths. While some of them are generalist and will eat a wide range of plants, most need specific host plants in order to reproduce, and those host plants are plants native to our region. Hence the connection between birds and native plants. 




Some native plant suggestions:

Trees:
Big leaf maple (host plant, nectar, seeds)
Dogwood (host plant, nectar, fruit)
Coastal Willow (host plant, nectar)
Bitter cherry (Prunus emarginata) (host plant, nectar, fruit)
Vine maple (host plant, nectar, seeds)

Bushes:
Coast black gooseberry (host plant, nectar, fruit)
Indian plum (host plant, nectar, fruit, early spring flowers for hummingbirds)
Flowering currant (host plant, nectar, fruit, early spring flowers for hummingbirds)
Ocean sprey (host plant, nectar, seeds)
Red elderberry - Sambucus racemosa (host plant, nectar, fruit)
Serviceberry - Amelanchier alnifolia (host plant, nectar, fruit)
Snowberry (host plant, nectar, fruit)
Nootka rose  - Rosa nutkana (host plant, nectar, fruit)
Red-twig dogwood -  Cornus sericea (host plant, nectar, fruit)
Dull Oregon-grape - Mahonia nervosa (host plant, nectar, fruit)
Salal - Gaultheria shallon (host plant, nectar, fruit)
Kinnikinnick - Arctostaphylos uva-ursi (host plant, nectar, fruit)

You can find a good list of native perennial plants at Pollinator pathway website.


And just one more thing: save energy to save the boreal forest! Logging, agriculture, mining, oil and gas, and hydro-electric development are rapidly increasing in the Canadian boreal forest, one of the largest intact ecosystems on the Earth. According to Boreal Songbird Initiative  nearly 50% of the 700 species that regularly occur in the U.S. and Canada rely on the boreal for their survival. For instance, an estimated 35% of the global population of the Varied Thrush, 45% of the Evening Grossbill, 47% of the Yellow Warbler and 68% of the Ruby-crowned Kinglet breeds in the boreal forest. Read more at the Canadian Boreal Initiative.