Since the original question had two points, about legal and moral standing,  I'll answer the legal part:

The short answer is NO YOU MAY NOT WITHOUT PERMISSION.

US law is both extremely clear and exceptionally vague.  The clear parts:
1.  Any new creative work that is set down in a fixed form is instantly copyrighted.  There is a bare minimum of creativity needed to generate copyrightable material.
2.  Dance choreography is a copyrightable form.

3. The following acts are SOLELY allowed to the copyright holder or specifically licensed user:  performance, reproduction, reprinting, publishing,  public display, broadcast, recording, creation of a derivative work.  I may have forgotten a few. 
4. US copyright law has no moral requirements; it is purely financial and transactional in nature.  You have no legal moral requirement (whatever that means...) to acknowledge the author's wishes or even identify them as the author.  In Europe this is different.
5. There is no mechanism established in US copyright law for a person to place an item into the public domain, nor for unclaimed and otherwise orphan works except if they clearly fall into the public domain due to age.  See Creative Commons for an attempted fix.
6.  If an item is not registered with the Copyright Office, you can only sue for actual damages and demand cessation.  (Usually neither worth it nor desired in our world.)  If an item has been registered with the Copyright Office, you can sue for many thousands of dollars, plus court costs and actual damages.

7.  There are no provisions for traditional or folk material or forms, and very little case law.

So, all modern contra dances are copyrighted works, and under the main part of the law it is clear that you may not legally publish, reprint, call (perform), or video tape them without permission from the copyright holder (this is not necessarily the author).

The unclear part:

The Fair Use provision allows for anyone to use copyrighted material without permission in any of the otherwise prohibited ways...under unspecified circumstances, according to at least four criteria that must be applied to each individual situation and weighted uniquely by a judge, and which can only be determined with certainty for a given case by the Supreme Court.  So, basically useless as a planning guide.

Whether you think the above should be true or not, it is correct based on the law. 

Feel free to ask questions.  I actually enjoy this stuff.

Neal