Any evaluation of historic ornithology for northern America would rely on archival and database information presented online. Without particular information, an adequate consideration would simply not be possible.
There are four primary sources worth recognition and accolades.
ORNIS - The Online Ornithological Information System
Provides a search option to many collections which contain specimen and egg records. This catalog can be "ornery" at times, but there are plans being considered for it to be upgraded, which will improve performance.
The Smithsonian Institution is included with the search option, though they also have their own online catalog.
Google Books
The sheer extent of information available here can be quite overwhelming. It requires focused searches, but often when an item is noted elsewhere, it can often be found in its entirety at this site. The options for searching using multiple words or terms is an essential tool. What is also valuable it that a series of items can often be perused, so if a particular article is part of a series, the other volumes can be reviewed to find the remainder of the information presented.
Online Newspaper Archives
There are two readily apparent online archives of newspapers which have details relative to birds which were published before there was anything like an ornithological journal.
Chronicling America has many newspapers from most of the United States. The most valuable aspect it the search option where criteria can be defined so as to return pertinent records. Paper pages are provided in PDF format, which makes them easy to view and print what might be of interest. This site is essential for its coverage presented for such an expansive geographic region.
The California Digital Newspaper Collection presents newspapers from 1846 to 1922, and is maintained by the University of California, Riverside. It is a wonderful source of information, with an easy to use search tool. Results are presented in a user-friendly manner which includes a snippet of the particular item, making it much easier to evaluate its content and any need to take a closer look. The few words are often enough to convey that the item does not have details for the topic.
The CDNC search results are preferable to the similar feature at the Chronicling America site where search results show the matching items in a pdf document, which requires further evaluation of the page. This requires downloading the entire page and zooming in to determine if the results are of any significance.
Search results for the California newspapers can also be evaluated based upon the type of item (article or advertisement and whether there is an associated image), as well as the year of issue. Providing different methods of sorting details is what makes this online service especially valuable. Each page presented can be viewed in a portable document format, which makes it an easy task to find something of interest and then get a printout for further consideration.
Efforts such as these have allowed research into the history of ornithology to expand to a whole new realm where a multitude of records, historic books or documents, and oldtime newspapers can be considered. These sources often contain records of species for a particular place and time. Early history newspaper often had details of bird occurrence during an era when there was no such thing as an ornithological journal.
These creation of these archives is one of the top developments in the study of birds which have become available during the past ten years. They surpass many other notable achievements for this period, and are absolutely a most essential aspect for anyone with an interest in the study of the fascinating details and nuance of historic ornithology.