Welcome to the thread! My opinion, if your rooster took on a hawk defending his hens, that is not a bad thing! Only if he is aggressive to people would I worry. Any people-aggressive birds get eaten at my farm. The hens fighting, now that is something I have not seen in my Marans, more than the usual squabbles that all flocks seem to have. There may be differences in bloodlines for sure in temperament and if yours were from birds more recently imported, they might be different in that way from a lot of the ones already being bred in the U.S. I read this thread off and on quite a bit and mostly what I have read is people liking the temperament of their Marans.I'm new this site as a poster so I'm not sure the past history of this page, but it sounds heated. I just wanted to get my opinion of this beautiful breed out there. I have a trio of French Copper Black Marans and they are gorgeous to be in no way self serving. I got my trio as a second crop from an original importer. My one hen has the flaw of having naked legs, but I lover her just the same. I have two major issues with my trio though, first my rooster is as violent as a game cock, ex. he took on a young hawk and won, second my hens are both food vacuums and very poor producers, about 160 eggs a year each. Not to mention the hens fight all the time too. These birds are beautiful, and you feel luxurious eating the eggs, they are the eggs James Bond, Sean Connery, eats in three of this movies and they are a fairly expensive in french restaurants, around 10 euros for one as Eggs Benedicta, that was the price the last time I was in country. With all this extravagance its no wonder do me that people who raise them cant help but feel a little posh. That being said, these chickens are not for a beginner and may be their own worst enemy for getting more breeders to raise them.
As far as not for a beginner, I whole heartedly agree with that if the goal is to breed them to the SOP because the Black Copper Marans color is extremely difficult to get correct. Can't say much about the other varieties since I don't raise them. Raising them just for backyard chickens, meat, eggs, or whatever is no big deal. They are just chickens.