When scientists speak of migration, they are usually referring to seasonal migration: the large-scale annual movement of all or some of a population between its breeding (summer) and nonbreeding (wintering) grounds. Migration is a cycle that some bird species repeat each year in response to the change of seasons, almost always based on the availability of food. Birds need to eat a lot to keep going, and they need even more food when they are feeding their nestlings. Access to food is critical during migration and when birds are raising young.

The need to feed and raise nestlings is the main reason many birds don't just stay in the warm tropics all year round. Although the tropics have a good climate, there is also a lot of competition for food. Going north in the summer offers migrating birds a huge explosion of food sources, such as insects. But it's a balancing act, because migration is dangerous and many birds die during their journey. Some bird species migrate, and others don’t (see table).

Tropical Residents


Temperate Residents

High survival rate (avoid hazards of migration and harsh winter weather)
Moderate survival rate (due to hazards of migration)
Low survival rate (due to cold and starvation)
Few young raised per year (food for young is less abundant)
Moderate number of young raised per year (due to abundant food in breeding areas)
Many young raised per year (due to abundant food)

To summarize, some birds don’t face the challenges of migration: some species stay in the tropics where they raise fewer young (tropical residents), and others face a hard winter but get first pick of the best nesting spots in the spring (temperate residents). Migrants risk the danger of migration, but have the benefit of raising their young in the food-rich temperate region without having to survive the winter there.


For researchers, birds are ideal objects of study for a whole range of scientific questions. Birds have world-wide distribution and they are abundant in species and rich in adaptation. And because they share their habitats with humans more than any other animal group, they act as important biological indicators. In 1962 her book Silent Spring, Rachel Carson brought to the public's attention the role of birds as indicators of environmental health, and more people got involved in conservation action. For Example, the pesticide DDT was linked to reproductive failure in birds, especially raptors, and was subsequently banned with public support. Since then, birds have demonstrated their importance as bioindicators and keystone species in ecosystems.

Bird conservation—the preservation, protection or management of birds and their habitats—aims to ensure the health of bird populations and the habitats on which they depend. Bird conservation has been a national priority in the United States since the early 1900s, when scientists realized that humans could negatively impact the long-term sustainability of bird populations. The biggest threats to birds in the United States and globally are habitat loss and degradation due to human actions. Without sufficient habitat, bird species cannot survive. Habitat conservation is a key component of conserving our birds. Each habitat is unique, facing distinct threats, and posing specific conservation challenges. Recent findings indicate that about one-third of North America's bird populations declined during the last half of the 20th century, and there is wide recognition that global climate change will affect habitats and the birds that depend on them. There is clearly a continued need for bird conservation at local, state, regional, national, and continental scales.

While the problem is large, we don't want kids to get discouraged: there's much hope! These lessons aim to engage students not only by helping them to understand habitats and bird migration, but also by empowering them to see themselves as part of the solution for bird conservation. For example, monitoring birds through citizen science provides important scientific knowledge about local areas and can contribute to understanding, conserving, and managing the earth's natural systems. By engaging children in local environmental monitoring and explicitly teaching them about its importance, we can empower students to see themselves as part of a positive force that is working to ensure healthy ecosystems locally and globally, now and into the future.

Science Process and Collaboration

One of the most exciting aspects of teaching science is engaging students in the process of discovery. Science is a particular way of understanding the natural world and is built upon our natural curiosity. We use our senses and extensions of those senses (instruments) to make observations and collect information about the world around us. Scientists always base their explanations or conclusions on evidence, using data from their investigations and experiments. But they have to stay open-minded and be willing to change or discard their ideas when new or more reliable evidence is found. Scientific results are always subject to testing and possible revision. The Scientific Process is commonly thought to be linear, with a straight forward starting and stopping point. It is much more three dimensional then this, with ideas and conclusions building a intricate matrix of knowledge.This Science can be especially fun because it uses creativity and imagination (with a good bit of logic thrown in)!

We want kids to understand science content, but we also aim to build students' critical thinking skills through participating in inquiry investigations. The goal of BirdSleuth investigations is to enable students to be real scientists as they identify useful research questions, design and conduct appropriate experiments, and then interpret, communicate, and justify their findings. Some students conduct research by examining eBird data, collected by birders around the country. Others ask questions based on their own bird observations and then carry out field studies to address their questions. Through such activities, students experience science as an exciting, dynamic process, and they learn that they can design and conduct investigations to address their own questions both in the computer lab and in the field.

external image i_wonder.gifAn "I Wonder" Board provides a way to track student questions throughout the investigations. Questions might arise during class that you can't explore because of time constraints, or because you are not sure how to address them, or because you want students to consider them more. Keep track of these questions on a class "I Wonder" list (this might be a bulletin board). Recording questions will eliminate pressure for you to provide immediate answers and might encourage students to think about or answer their own questions. You'll also prevent the problem of losing questions in the "Thats a great question .. let's come back to it later" vacuum. Some teachers have given kids post-it notes to keep handy for recording questions to place on the board.

If you have time and interest to go further with student investigations, we've developed BirdSleuth:Investigating Evidence a complete set of online lessons that will help teachers guide their students through the processes of observing birds, asking questions based on observations, gathering data to address questions, and sharing findings in a student research journal. This optional unit help you and your students conduct your own investigations about birds, perhaps addressing some of the "I wonders" your students have come up with. Progressing through the five lessons in the Investigating Evidence online module, students start by considering what is science and finish by presenting the results of an investigation that they have designed and conducted to address a research question of their choice. This free module includes lesson plans, journal pages, and online resources that will help your students ask scientific questions, craft and test hypotheses, collect and organize data, draw meaningful conclusions, and publish their work.

Citizen Science

Citizen Science is a partnership between scientists like the ones at the Cornell Lab of Ornithology and the public, including people like you! Citizen Science is quickly becoming a powerful tool for scientists to answer continental questions, and teachers showing students how to observe their natural surrounding is among the first steps towards creating the next generation of citizen scientists. Remember, even if your students can't identify many birds, accurate observations is the first steps towards creating a valuable citizen scientist.

Through the Cornell Lab’s citizen science projects, people around the world collect data about their local birds and contribute these observations to databases that are used by researchers, students, and the public to better understand bird distribution, abundance, and population trends. Citizen science works because a lot of people, like the children in your group, are knowledgeable about birds and enjoy watching them! Cornell Lab offers a variety of citizen science projects (such as Celebrate Urban Birds, YardMap, NestWatch, and Project Feederwatch) which differ in the kinds of information we people to collect. Developing a local bird count, whether in the schoolyard or another local area, is a great way for your students to better understand local bird species and to participate in the protection of birds! It is also an ideal opportunity for a science inquiry lesson based on field study. For students, participation in citizen science projects is motivational because their data are put to use addressing real-world issues of local and global concern.

The eBird citizen science project is one of the world’s largest and fastest growing biodiversity data resources, currently receiving over one million bird observations per month entered by participants. This project asks people to conduct a local bird count (for as long or short a time as desired) and report the kinds and numbers of birds they see. Because of its flexible nature and the fact that data can be collected anywhere in the world in any habitat, eBird is popular among educators. In addition, students also can use the outputs of the eBird database to investigate intriguing questions about bird abundance and distribution at a variety of spatial and temporal scales.

A citizen science handout, describing three projects that are popular with teachers (eBird, Project FeederWatch, Celebrate Urban Birds) can be found in the resource pages.