You might want to have a look at the Codex Canadensis, by the Jesuit Louis Nicolas. It includes a collection of drawings realised from 1664 to 1675 focussing on wildlife, native life and a first contact with the natural history of the Americas. The artwork combines watercolor and charcoal, and a bit on the coarse side by modern biological artwork standards.

The Codex is believed to be intended as the plates and illustrations meant to accompany the main work of Nicolas: the "Histoire Naturelle des Indes Occidentales", where you may find additional info you may want to tap into.

They can be found together in the following edition:

Louis Nicolas, sous la direction de Francois-Marc Gagnon et de Nancy Senior, The Codex Canadensis and the Writings of Louis Nicolas: The Natural History of the New World / Histoire Naturelle des Indes Occidentales, McGill-Queen's University Press (Presse universitaire McGill), Montréal, Québec, Canada.

The plates are however available online here:

https://commons.wikimedia.org/wiki/Category:Codex_canadensis?uselang=fr

I've got to say: I love his map of the Mississippi river and surrounding area (termed "Manitounie" by the author), with the rattle snake sketch (last plate, right after all the animals and fish plates).

There is also quite a bit of info available in the Journals of Jacques Cartier (although obviously not strictly speaking a work of natural history) for the 1534 to 1542 period, provided you are willing to wade into it and "go fishing for data". He describes about 50 different kinds of plants here and there throughout his work, often with some ethnobotanical data relating to uses by the Iroquois. His perspective is of course that of selling France to the idea of setting up a colony in New France, so there is at time a bit of a "salemanship" type of bias in the descriptions, but there are plentifull descriptions of natural settings, vistas and fauna and flora.. They are available online.

By far the best source for this is William Cronon's Changes in the Land; the whole first section is a discussion of what European settlers saw and did not see in the landscapes. His work will point you toward a whole range of primary sources on American landscapes. He also documents species change in great detail, so I think it's exactly what you want.

What you will NOT find, however, is "wilderness"--the Americas were totally populated. There was no land that did not bear the marks of human occupation. As Cronon himself argued in a later essay (the guy basically invented the "environmental history" as we know it in the US), "wilderness" is a construction, a thing that European-Americans imagined and then made a reality, largely by evicting Native Americans from lands that they declared "wild."

Another relevant text for this topic is Richard Grove's Green Imperialism, about the encounters between European doctors, naturalists, and administrators, and the landscapes they found in the world beyond Europe.

You should also be aware that "scientifically correct" is a moving target--it's based on what you think is correct at the current moment. If you asked people what views of the historical ecology were "scientifically correct" in, say, the 1910s, you'd get very different answers from today. And, based on the history of scientific knowledge broadly, that answer will be quite different again if you were to ask someone in the 2110s.

Adriaen van der Donck was a Dutch settler who traveled quite a bit around upstate New York during his time working at Rennselaerwyck, then settled in New Amsterdam. He wrote his Description of New Netherland in 1655, which covers beaver in great detail, but also briefly surveys the whole animal kingdom, including animals like mountain lions and buffalo that don't range up to the Hudson River area but whose skins travel as trade items. One should keep in mind that the Description was intended in large part to attract more settlement, so he had a reason to play up any lucrative opportunities and downplay dangers. Also, the 1841 translation that is freely available online was done by someone with inadequate knowledge of seventeenth century Dutch who really muddled things up in places. There is a much better 2008 translation.

The works of John White and Thomas Hariot may be what you are looking for.

White and Harriot were both part of the infamous attempt to colonise Virginia in 1587 (the "Lost Colony"). The former painting a large number of water colours and sketches of the Powhatan indians and their environment while the later wrote A brief and true report of the new found land of Virginia.

Much of what we currently know of the coastal algonkians/algonquians come from White and Harriot (sometimes also spelt Hariot), particularly with regard to their material culture (i.e. clothing and ornaments) and their settlements.

EDIT: Again restricted to the Eastern Seaboard, but this time the piedmont rather than just the coast, John Lawson's A New Voyage to Carolina could help you. While I do not think that Lawson is a completely trustworthy source, particularly with regards to some of his assertions about areas further away from the route of his journey, he does write a lot about the animals and landscape through which he passed.

It depends on what kind of wilderness you want. John Smith, English explorer, wrote a large number of descriptions of the wilderness he saw but it was mostly confined to the coastal wilderness