Jamieson, Fausset and Brown on Leviticus 11:13-19

13-19. these are they which ye shall have in abomination among the fowls--All birds of prey are particularly ranked in the class unclean; all those which feed on flesh and carrion. No less than twenty species of birds, all probably then known, are mentioned under this category, and the inference follows that all which are not mentioned were allowed; that is, fowls which subsist on vegetable substances. From our imperfect knowledge of the natural history of Palestine, Arabia, and the contiguous countries at that time, it is not easy to determine exactly what some of the prohibited birds were; although they must have been all well known among the people to whom these laws were given.

the ossifrage--Hebrew, "bone-breaker," rendered in the Septuagint "griffon," supposed to be the Gypoetos barbatus, the Lammer Geyer of the Swiss--a bird of the eagle or vulture species, inhabiting the highest mountain ranges in Western Asia as well as Europe. It pursues as its prey the chamois, ibex, or marmot, among rugged cliffs, till it drives them over a precipice--thus obtaining the name of "bone-breaker."

the ospray--the black eagle, among the smallest, but swiftest and strongest of its kind.