Twice a year Vaux’s Swifts roost in the chimney at Frank Wagner Elementary School in Monroe, Washington. Once a year the school hosts ‘Swift Night Out’ where people come visit from all over the state, and even country to watch the swifts descend at dusk into the school’s chimney. There are educational booths from groups like local Audubon chapters and there is a swift expert who gives a talk. The 4′x4′ chimney is no longer used to heat the school and is now left to the swifts. It was recently retrofitted to make it earthquake safe for the school and their bird visitors. Seattle Audubon helped the school receive a grant which is used to bring in a special program to educate the students about the swifts. Thanks to the swifts the kids learn about geography, math, biology and science from first hand experience.Continue reading »
Running now through May 15th of 2011 is Presidio Habitats in San Francisco. It is a joint venture between FOR-SITE Foundation and Presidio Trust and started running May 16th of this year. The Presidio has a long and interesting military history starting in 1776 with occupation under Spain followed by Mexico and finally the United States up until 1994. It is now a 1,491 acre national park with the Presidio now a National Historic Landmark District comprised of 469 historic buildings. The historic landscape is also part of the National Historic Landmark District and includes a historic forest which was army planted, transforming the dunes into a 300 acre forest. Today Presidio is valuable wildlife habitat in the city and is home to many species of insects, reptiles and amphibians and bats and small mammals and as many as 200 bird species, as you can see from the video below. Despite the number of species now, the Presidio is also known for a more tragic story of wildlife, being the last place the now-extinct Xerces Blue butterfly was ever seen.
The Presidio Habitats exhibition was launched in 2009 with the international invitation of artists, architects and other design professionals to submit proposals for wildlife species traditionally found in the Presidio. Eleven were selected out of 25 to be installed for a year in the park. The tour begins with the exhibition pavilion, a construction out of three reclaimed shipping containers “arranged at 120 degrees around a central atrium.” The first of the artwork is ‘Where is the Hare’ by sculpture and performance artist Nathan Lynch and features the Black-tailed Jackrabbit which is currently absent from the park. The art installation is “an imaginary footrace intended to appeal to the hare’s mythologically well-documented sense of pride in its own dexterity and speed.” Another past inhabitant of the park was of course a turtle, the Western Pond Turtle specifically.
This was mentioned in a recent Foragings post, but it has such great design implications that I wanted to feature it in more detail.
Over several years a landowner has turned previous agriculture land into a wetland habitat. Natural England helped with this transformation through their Higher Level Stewardship program which “aims to deliver significant environmental benefits in high priority situations and areas”. The program offers advice and and support to landowner’s for “more complex environmental management”. The most recent work at the site was the building of a wall sited to offer nesting for different bird species including the kingfisher and sand martin. Both of these bird species have Amber status from the RSPB which is the mid-level status for conservation. There are nearly 200 holes in the wall designed for the sand martin while two are designed specifically for the kingfisher and are the first in the country to be so.
While the sand martins aren’t expected until 2011, a kingfisher has already moved in and successfully reared a brood of six chicks. Dr. Nigel Russell from Natural England states the significance of this event: “This first brood of kingfishers is great news for a site that was reverted to wetland just four years ago. The presence of breeding kingfishers is recognised as an indicator of high quality wetland habitat.”
The property owner gave his thoughts on the kingfishers, “It is a privilege and thrill to host such iconic birds so soon after completion of the nesting colony. They appeared as if by magic within weeks – unmistakeable in their orange and shimmering blue plumage.”
While this is not an urban site, this project could potentially be replicated in urban settings such as along rivers or other urban wetland and riparian sites. Many towns and cities have rivers or creeks running through them as do many individual neighborhoods. While the species attracted may vary depending on the location, the idea of providing these nesting walls offers a valuable habitat design tool. Many cities have channeled the rivers that run through them and as more cities attempt river restoration projects, this idea may be an option. Where there is already existing infrastructure such as bridges or retaining walls, nest holes could potentially be incorporated into the existing structures or added onto them. Coupled with the idea of floating islands (which was covered here, Floating Habitat Islands), cities could use these tools as an option for restoration that offers options to do so without dramatic structural changes. This could be a short term solution until a major restoration project was implemented, or in situations where it’s not feasible or economically viable for a full restoration.
A similar idea, featuring nest boxes along a water way, was featured here with an interview with the designer: Animal Wall in Cardiff Bay.
This is my comprehensive project that I completed in my final year of the Landscape Architecture program at the University of Oregon. The two-term project was the culmination of my educational career and I wanted to choose something meaningful that would relate to my main interest of creating and designing urban wildlife habitat. I started to ask around and very quickly a project fell into my hands from Mike Houck, the Executive Director of the Urban Greenspace Institute in Portland. He has been responsible for creating Oaks Bottom Wildlife Refuge as well as a giant mural on the side of the Portland Mausoleum that overlooks Oaks Bottom Wildlife Refuge, and had been interested for some time in creating a green roof for the building. I was lucky enough to also consult with Bob Sallinger, Conservation Director for Portland Audubon as well as Tom Liptan from the Bureau of Environmental Services, City of Portland and local eco-roof expert. In addition I talked with the building manager for the Mausoleum.
This project was a challenge because no plans for the building existed, they had all disappeared, so no measurements or structural information were available for the design. Instead I had to take some measurements and measure the rest from Google Earth.
Read through the presentation with the script added in, for a full detail of the design including goals, hypotheses and design reasoning.
Retaining walls are a fact of life for many landscapes, even those with only a slight slope. The majority of walls however, are constructed as a flat surface, stones bound together with mortar which don’t serve any benefit to wildlife. Stone walls however, can be quite beneficial for wildlife if designed and constructed correctly. Even if a retaining wall isn’t needed, rock shelters could be constructed in a similar manner. A rock wall, with crevices between the rocks add additional places for plants to grow and places for a variety of wildlife to take refuge in from the weather, predators, and further provide somewhere to raise young. Ground nesting bees could find space between the rocks to build their nests, cavities can be planned inside for mammals to hide or even hibernate, and small crevices can be an ideal shelter for reptiles and on lower, damper levels, amphibians. Other wildlife species that could benefit from rock shelters or rock walls include birds such as wrens, sparrows and towhees, small mammals such as squirrels, rabbits, chipmunks and insects such as beetles and butterflies.
Not surprisingly, there are not a large number of references for this topic which is unfortunate. Three books have good information about building stone walls in place of traditional retaining walls. The first is my go-to book, Landscaping for Wildlife in the Pacific Northwest. Chapter 15 covers brush and rock shelters in great detail and highlights how to plan for and build rock walls and similar structures. It also discusses how wildlife species make use of shelters such as toads who shelter in cool nooks waiting until it turns dark to emerge and hunt around the wall. Placement is important to consider depending on the climate, a wall that gets more sun versus a wall that gets more shade can make a lot of difference. Also important are what elements are around the wall such as plants, a pond, or elements such as a brick chimney that store heat and disperses at night. The book also has some good instructions about how to build the shelter or wall describing what types of rocks to use, how to create interior cavities with ceramic, plastic or concrete pipes and how to maintain temperature and humidity inside the wall. One of the highlights of this book is a diagram of a rock shelter.
Another good resource is the book Natural Landscaping: Gardening with Nature to Create a Backyard Paradise which gives a lot of great detail about how to build a rock wall. For example the main tip in most resources is “lay one over two”, meaning a stone on the layer above should be centered over the junction between the two stones on the layer underneath. Another universal tip is to slope the wall slightly back towards the hill behind it. This book includes good illustrations of the construction of a basic rock wall, but doesn’t address the idea of the previous reference, creating interior cavities. It does however, have some good calculations on how to gather the amount of materials needed. In addition, there are some excellent photo examples of rock walls.
Although this isn’t a very prevalent topic yet, there has been an increase of use of gabions in the landscape, which are essentially wire mesh square cages filled with stones. For the most part they’ve been used for soil erosion along steep banks and streams. Many landscapers are adding other components to the cages such as logs or even recycled plastics. Despite what the wire cage is filled with it’s still not necessarily an aesthetically pleasing landscape element although, as can be seen in this image, they do have potential to be very creative. They’re certainly starting to take on a new shape and function recently instead of being solely functional, they’re being used as an artistic piece to be aesthetic and functional. They’ve even turned up at the RHS Chelsea Flower Show. Where a rock wall filled with nooks and plants can fit into a natural landscape or even a traditional residential landscape, the gabions have the potential to take a habitat element a more artistic route.
This wall is in my neighborhood and I walk past it regularly. While it may be a little too wild for some landscapes, this wall greatly enhances this particular landscape which is the front yard of an older, brick, single-story apartment building. It creates a nice stroll along the sidewalk and fits in a great many more plants than would otherwise fit in this very small space. At some places the plants are so thick the wall can’t even be seen, while at others the large stones peak through the plants. Ferns, flowers including fuchsia and foxgloves, groundcovers and even shrubs fill up this space with a variety of color and texture. During walks I routinely see a variety of bees and butterflies visiting the wall. While it’s location along a street and sidewalk is not ideal for small mammals or reptiles and amphibians, it still serves a valuable habitat function for the variety of insects who visit it.
Swifts are one of the few birds that can draw crowds like rock stars. Their roosting is one of the greatest migration wonders of the natural world and they often choose to share it with us in the urban world. Several species of swifts are well known to roost in chimneys, often where many people have a chance to watch them. On the west coast of North and Central America Vaux’s Swifts roost in chimneys along their migration route. East of the Rockies, a similar species, the Chimney Swift does the same thing. They roost communally, often by the thousands and they all descend into their roost site at the same time creating a huge spectacle. At several urban sites people will gather numbering from the tens to the thousands to watch the swifts descent into a chimney. In Europe and Asia the Common Swift is a familiar city sight and they range as far north as the Laplands, as far east as China and spend their winters in Africa. In the UK the Swifts commonly nest in roofs and not in chimneys, but very often in urban settings. You may remember a post a short time ago about nest boxes, roofs and swifts in the UK, Not Your Traditional Nest Box.
American Swift by John James Audubon
In the cities, these birds make choice of a particular chimney for their roosting place, where, early in spring, before they have begun building, both sexes resort in multitudes, from an hour or more before sunset, until long after dark. Before entering the aperture, they fly round and over it many times, but finally go in one at a time, until hurried by the lateness of the hour, several drop in together. They cling to the wall with their claws, supporting themselves also by their sharp tail, until the dawn, when, with a roaring sound, the whole pass out almost at once. Whilst at St. Francisville in Louisiana, I took the trouble of counting how many entered one chimney before dark. I sat at a window not far from the spot, and reckoned upwards of a thousand, having missed a considerable number. The place at that time contained about a hundred houses, and no doubt existed in my mind that the greater number of these birds were on their way southward, and had merely stopped there for the night.
–John James Audubon, Birds of America
Swifts are small birds, similar to Swallows, who spend the majority of their day catching insects. In fact a single Swift can consume as many as 20,000 insects in a single day. They will never land on a tree branch or power line because their feet are not equipped to do so. In North America, both species would naturally nest and roost in hollow trees, with the same descending spectacle, but Chimney Swifts, and to a lesser extent Vaux’s Swifts, have started to make use of chimneys. Vaux’s Swifts may become more dependent on chimneys if their preferred old growth habitat is lost. Their nests are made of small, dead twigs in an open, half circle and are attached to the inside wall of trees or chimneys. The Vaux’s Swift is a surprisingly unstudied bird and many aspects of the life history are still unknown. Also for reasons mostly unknown, all three species population numbers have been in recent decline.
In Monroe, Washington a few thousand swifts have been recorded to roost in a school chimney while in Portland, Oregon at Chapman Elementary School as many as 40,000 funnel into the chimney at sunset every night during their stay, twice each year, while migrating. There are many more swifts during their southbound migration because all of the new, juvenile birds now travel south with their parents. Here is a good video from Oregon Field Guide on Oregon Public Broadcasting that talks about the swifts and their roosting in Chapman Elementary School.
This year Vaux’s Swifts have appeared to take up a similar residence in L.A. surprising a number of local residents by their extremely urban location choice. The Chester Building, an 84 year old, 12 story building constructed in 1926 includes an adjacent, abandoned brick chimney where the birds took up residence on their northbound migration in the spring this year. Unfortunately in L.A. many old, brick chimneys are being torn down because they don’t meet earthquake codes. Newer chimneys are smooth and insulated which are unfavorable for the swifts because they can’t grip the smooth surface.
Like the Vaux’s Swift, Common Swifts have also been in decline in Europe and Asia. There are efforts to save swifts in London and even in the Czech Republic where it was named the bird of the year a few years ago. Beijing has also seen a steady decline in swifts in a city where they have been so prevalent since the 13th century that another name for the city was Yanjing(燕京) or Swift Capitol. Ironically, the Birds Nest stadium and other stadiums which were built for the Olympics were all non-friendly swift buildings.
Protecting the swifts by protecting chimneys is one way to help the birds along their migration route. In some cases however many are finding the renovation and/or maintenance costs prohibitive, especially when trying to meet earthquake safety codes. Some groups are already creating alternative structures for swifts to roost in such as is the case with Chimney Swift Conservation Project, in Minnesota. The project, spearheaded by Audubon Minnesota, partners with a variety of groups including schools, parks, corporations and individuals, to construct towers and educate people. They have successfully installed a number of towers in a variety of locations, some of them local schools which in turn look at them as a new source of education. There are similar efforts in New York City by Audubon New York who have successfully placed swift towers in all five boroughs. In North Carolina individuals can apply for a grant from Wildlife Rehabilitators of North Carolina to build swift towers. People who have already applied and installed towers are being rewarded with successful nesting in their towers.
Swift Tower in Washington via:: The Nature Conservancy
Vaux’s Swifts are getting similar treatment west of the Rockies, as can be seen with this tower, built by an Eagle Scout in partnership with The Nature Conservancy in Washington. The Nature Conservancy also partnered with the Department of Defense to install towers at Fort Lewis, also in Washington.
There are some good resources for the construction of swift towers, one such is Providing and Maintaining Nesting Habitat for Chimney Swifts (PDF). These towers have been placed in 20 or more states so far. There is also a book dedicated to the subject of swift towers and how to construct them: Chimney Swift Towers: New Habitat for America’s Mysterious Birds.
It’s wonderful that we can share our buildings with such amazing wildlife and it’s even more amazing that so many people are interested in them. The overlap of the urban life and the natural world can be a wonderful thing, especially when the spectacle attracts hundreds if not thousands of people, looking for a way to connect to that world. It’s an ideal situation for learning, bonding and conversation.