Impacts of Rain Gardens on Urban Bird Diversity

Rain gardens have proven to be a useful tool to mitigate stormwater run-off in cities. They are depressions on the side of the road or sidewalk with plants that absorb rainfall and prevent water from picking up pollutants and carrying them to the nearest stream. The plants and soil also filter the water. But this is not the only service rain gardens provide, the diversity of plants used in them increases habitat for many animals. Many insects and spiders are drawn to the local plants and they in return attract birds and small mammals. Rain gardens can provide nice shelter for these animals too.

As part of project “BluePrint” the City of Columbus plans to install some 500 rain gardens in the Clintonville area to manage stormwater runoff. Dr. Jay Martin, Professor of Ecological Engineering at OSU joined the project to holistically quantify the impacts of stormwater green infrastructure on societal services such as stormwater management, public health, community behavior, economics, and wildlife habitat. Dr. Martin’s PhD student David Wituszynski focuses on the animal aspect and recently contacted the Borror lab to discuss his research idea. David wants to test the hypothesis that implementation of such a large network of rain gardens will increase the diversity of urban bird species.

SongMeter mounted (

SongMeter mounted (

Specifically, he wants to develop automated acoustic methods to track urban bird populations. He will deploy SongMeters, automated recordings units, and program them to record surrounding sounds at certain times of the day. It is easy to record thousands of hours of bird and insect sound, but one needs to analyze them afterwards and identify vocalizing species.

This takes us back to the problem of automated sound recognition raised in Monday’s post. Dr. Martin and David are collaborating with Don Hayford from Columbus Innovation Group who will develop techniques to filter out background noise (such as human voices, machinery, cars, barking dogs – all familiar sounds to our neighborhoods) and produce files of target sounds that can then be analyzed with existing software.

My role will be to provide reference sounds for the software as we need to train the software to recognize known vocalizations of local bird species. This is not an easy task because some bird species have quite varied vocalizations. Our large and diverse archive of sound recordings will come in handy, we have many recordings of local Ohio species. These should cover most of their diverse vocalizations. Our goal is to build classifiers that automatically recognize and label species in the recordings.

map of Clintonville area with proposed rain gardens (project BluePrint, Columbus OH)

Will you get a rain garden on your street? check this map

We have just submitted a grant application to help us fund some of this research. The first SongMeters will be deployed this fall and we will start monitoring the areas to get a baseline level of bird activity. Come spring the city will install rain gardens in the neighborhood and we can compare our recordings before and after the installation. This certainly is a multi-year project. We will keep you updated.

Should you see a rain garden in your neighborhood, take a picture and share it on social media #BLB #raingarden #songmeter!


Further resources:

The project BluePrint was featured in the Columbus Dispatch last January!

Learn more about rain gardens in Central Ohio!


About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics at OSU and Co-PI on the project “Determining Impacts of Rain Gardens on Urban Bird Diversity” with Dr. Jay Martin, David Wituszynski and collaborator Don Hayford.

Striking Out: Building Strike Collections

Students and staff posing with birding binoculars and scopes

OSU students and staff participating in Biggest Week in American Birding in Northern Ohio. ©Stephanie Malinich, 2012

As a bird-watcher, spring is my favorite time of the year. Every spring millions of birds start to migrate from their wintering grounds to their summer breeding grounds. Surprising to most people, many birds migrate at night and typically you will not see large flocks of small birds traveling throughout the day. Spring migration can be a great time to see new species of birds that may not live in your state year round and this is a time for celebrating birds. But this joyous time for birders can also be an incredibly fatal time for birds that have traveled thousands of miles on their migratory pathway to their nesting grounds.

An estimated 500,000,000 bird fatalities occur in North America each year due to anthropogenic sources including collisions with building (Erickson et al 2005). Yes, this is correct, 500 million birds! This number is especially heightened by the peak migration times of spring and fall, when birds migrating at night are most likely to die: Night migrating birds have always used light to orient themselves and usually the moon and stars are the only light sources in the night sky. However nowadays brightly-lit buildings disorient these birds causing them to collide with windows in buildings. Typically, birds are trying to closely approach the light source (similar to insects around a street lamp) or circle the light source (in this case the building) until a point of complete exhaustion.

Yellow colored warbler with black bill

A Blue-winged Warbler collided with a downtown Columbus building. © Stephanie Malinich, 2016

This makes building collisions a top fatality to birds on their migratory pathway. Actions since this discovery have been taken to lower the numbers of building fatalities, e.g. through the national effort of  Lights Out programs by the Audubon society. The overall goal of the Lights Out programs are to work with building managers in major cities to reduce the amount of light at night during peak migration season. Not only will this help reduce fatalities for nocturnally migrating birds but reduce energy costs for building owners – a win-win situation.

Many of Ohio’s major cities such as Columbus, Cleveland, Dayton, and Toledo have participated in Light’s Out Programs. Active in Ohio since 2012, researchers have worked with managers of some familiar buildings such as the AEP corporate headquarters, Columbia Gas, Columbus City Hall, Grange Insurance Audubon Center, and more on reducing lights at nights during peak migration seasons. Are you curious about Columbus’s impact on bird building collisions? Columbus Lights Out monitoring report from 2012-2013 gives insights into how lights on buildings in Columbus are affecting the amount of collision death and injury in birds.

Dead bird on sidewalk

Blackburnian Warbler collected by Lights Out Columbus volunteers for a study of building collisions. ©Lights Out Columbus, 2013

What do programs such as Lights Out, which survey injured and dead birds, mean for museum collections around these major cities? For Columbus it meant that birds found dead were submitted to the Museum of Biological Diversity’s Tetrapod Collection, where they are now used as tools in teaching students and making them aware of the impact buildings can have on bird populations. In the two years when we collaborated with the Columbus Lights Out program we received over 200 bird specimens which had died from building collisions in downtown. These now remain as vouchered specimens in our collection, as physical proof, as well as scientific tool, on the impact that building collections have during migration season.

Overall as collection manager, I see a huge increase in our bird salvage intake during spring. This is primarily due to citizen scientists who find birds that have struck windows on their house, work buildings, etc., and want to make sure the birds death was not in vain. On average the Tetrapod collection receives close to 100 bird specimens with suspected death from building collision each year. This April and May alone, I have already received 15 bird species that have died from impacts with windows or buildings and spring migration is not yet close to completion. If you find a dead bird and do not  know what do with it, please visit the museum’s Contribute Specimens webpage to learn about how to donate a specimen to the Tetrapod Collection. Are you worried that your home may be adding to building fatalities among birds? The Lights Out program has suggestions on how you can stop bird collisions at your home or feel free to contact us for some suggestions.
Are you curious to find out more about what can be done to make others aware of window or building collisions by birds during spring migration? See pictures of what Ohio State University’s BioPresence project has done to raise awareness in their art exhibition last fall.


About the Author: Stephanie Malinich is Collection Manager of the OSU Tetrapod Collection.


Reference: Erickson, Wallace P.; Johnson, Gregory D.; Young, David P. Jr. (2005). “A summary and comparison of bird mortality from anthropogenic causes with an emphasis on collisions.” In: Ralph, C. John; Rich, Terrell D., editors 2005. Bird Conservation Implementation and Integration in the Americas: Proceedings of the Third International Partners in Flight Conference. 2002 March 20-24; Asilomar, California, Volume 2 Gen. Tech. Rep. PSW-GTR-191. Albany, CA: U.S. Dept. of Agriculture, Forest Service, Pacific Southwest Research Station: p. 1029-1042

Time travels with the Borror Lab of Bioacoustics

Carolina Chickadee by Dan Pancamo

Carolina Chickadee by Dan Pancamo

One thing that is unique about the sound archive of the Borror Laboratory of Bioacoustics is that it not only contains a wide diversity of animal sounds, but a great number of recordings for certain species. When I started my Ph.D. research here at OSU, I was pleasantly surprised to find that this depth of recordings also included one of my study species, the Carolina Chickadee (Poecile carolinensis).

The namesake of the Borror Laboratory of Bioacoustics (BLB), Dr. Donald J. Borror, was one of the first biologists to take recording equipment out into the field to record animal sounds. And he started in and around Columbus. Because Carolina Chickadees are rather common birds here in the central and southern portions of Ohio, Carolina Chickadees were some of the first animals Dr. Borror recorded. The oldest recording he archived in the collection dates back to 1948. Listen to a 30-second excerpt of Dr. Borror’s recording of a typical four-note whistled Carolina Chickadee song from April 1948 (note: You can listen to the entire recording (BLB21) on the BLB’s website):

You may not think that having all these chickadee recordings across a long time period is super duper exciting, but I do. See, I study chickadee song. And we know that chickadees, like other songbirds, learn their song: young chickadees must hear other individuals of their species singing and imitate those sounds in order to produce normal adult song. However, like learning in humans, song learning in birds is not always a perfect process. As young birds make imperfect copies of the songs of the adult birds they hear, variation is introduced into the songs of a population of birds. Think about how the English language has changed in the past 100 years – some words have stopped being used, new ones have come into fashion – this is analogous to what happens with song in bird populations.

The end result is that not every chickadee sings exactly the same song and the acoustic traits of chickadee songs can change slightly from generation to generation. Using the BLB collection I can actually look at how Carolina Chickadee song has changed in the Columbus area over the past 65+ years.

What you are going to see below are a series of maps with representative spectrograms of chickadee songs from all over Columbus for different decade ranges. If you have never seen a spectrogram before, it is essentially a visual representation of sound, with time on the x-axis, frequency (or pitch) on the y-axis, and the darker color representing more energy (or the loudness) of the sound. Here is the spectrogram of one song of a Carolina Chickadee from the 1948 recording by Don Borror above:

Spectrogram of one song of a Carolina Chickadee recorded by Don Borror in Columbus OH in 1948

For each map below I encourage you to visually compare the different chickadee songs using the spectrograms (I have left the axes off for simplicity’s sake) and then listen to the recording containing those songs using the links below each map. Any overlapping spectrograms are from the same individual bird: Carolina Chickadees can sing up to 4 different song types each, although most only sing one or two types. If you want to listen to the original recording archived in the BLB, please click on the link for each BLB cut number.


As you can see, Carolina Chickadees usually have a four-note song of alternating high and low whistled notes, but check out the weird song at Blacklick Woods Metro Park (#3)! Dr. Borror’s 1948 recording is actually quite unique in that the notes in the chickadee’s song are not very different in pitch from one another; usually Carolina Chickadee songs sound and look more like the spectrograms seen in examples 1 and 4b.


#1 (BLB1354)

#2 (BLB2451)

#3 (BLB3909)

#4 (BLB3947)



map2The unique song type seen before persists at Blacklick Woods Metro Park through the 1960s. Also note that some Carolina Chickadee songs start with a note much lower in pitch than others (like song number 1 here, or song 4a in the 1950s map). Carolina Chickadees also sometimes add notes onto the end of their songs, resulting in five-, six-, and sometimes up to twelve-note songs, although they usually keep the alternating high-low pattern (see #4).


#1 (BLB6374)

#2 (BLB9942)

#3 (BLB5112)

#4 (BLB9026)

#5 (BLB7966)



Many of the songs in this decade are very similar, but one individual at Blendon Woods Metro Park (#2b) showed an interesting song with an additional introductory note. This song type is not seen in any other bird in any other decade, so it is possible this song type was never sung by any bird but this one.


#1 (BLB11032)

#2 (BLB14217)

#3 (BLB13312)

#4 (BLB11030)


map4As you can see, not much song variation was recorded in the 1980s, except for that three-note song up in Delware. While most of the songs follow the typical high-low-high-low pattern, there are subtle differences between individuals, like in the downward sweep of the first note.



#1 (BLB17075)

#2 (BLB17078)

Note the Black-capped Chickadee singing in the background of recording #2:

#3 (BLB15737)

#4 (BLB17063)



In Delaware a three-note song type persists in the population from the 1980s into the 1990s. Also, the song type that starts with a lower-pitched note continues to pop up in various areas of northern Columbus (e.g. 3b), but is not seen in the southern portions of the city. Interestingly, I had not heard that song type myself while living in Columbus until moving to Clintonville this past March; up near Dublin that song type is not common anymore.


#1 (BLB17435)

#2a (BLB17433)


#3 (BLB21124)

In the past 14 years none of the recordings in the BLB collection specifically target Carolina chickadee songs. It would be interesting to know if those strange songs from Blacklick Woods Metro Park are still sung in that area, or if any other unique song types have appeared in the Columbus area.

So, as you travel throughout the Columbus area, keep an ear out for some odd chickadee songs … you may even hear something that has not been recorded before.

About the author: Stephanie Wright Nelson is a graduate student in the department of EEOBiology. She studies song learning in chickadees and is particularly interested in the consequences of hybridization between Carolina and Black-capped Chickadees.