A field notebook is a notebook which is used by a researcher to take notes while out in the field. The goal of the notebook is to create a complete record which provides accurate and useful information about field expeditions, and scientists who work in the field are usually required to keep such notebooks. In some cases, field notebooks are considered the property of the employer, in which case a researcher will have to submit them once a field study is over, while in other cases, the notebook may be the property of the author.
In addition to professional scientists, many amateurs also keep field notebooks. A birdwatcher, for example, would keep a notebook of bird sightings which also included data about locations, weather conditions, birding partners, and so forth. By reading the field notebook, someone could get a complete picture of what happened on any given expedition. In fact, someone should be able to read a field notebook and feel like he or she was along for the trip, thanks to the high level of detail provided.
Every single piece of data related to an expedition is recorded in a field notebook, along with general observations. Something which seems less important in the field might actually play a key role in a study or expedition upon later examination, and by recording it, a researcher ensures that it will be noted. Sometimes, a perusal of a series of field notes can reveal the answer to a mystery, as for example when a birder notices that flocks of birds consistently rise out of a certain patch of trees every day at 10:03 AM, and someone mentions that a supply plane lands just behind those trees every day at 10:02 AM.
Typically, field notebooks are hardcover, and many are made from papers which are designed to be water resistant. Researchers carry their notebooks in bags or cases to prevent them from getting wet. The notebook is usually ruled, and it contains recorded observations and measurements, sketches, general notes, discussions of weather conditions, and any other errata which might be relevant to the study, from where cars were parked to who was in the field on any given day.
Scientific supply companies often carry standardized field notebooks, and notebooks can also be purchased from stationery suppliers. Scientists who work for particular companies or organizations may want to find out if the company has a preference for a particular type of field notebook, as the need for organized storage may dictate a specific size or style. Some companies issue field notebooks to their employees for this reason.