Regional Jet 200 ER/LR (CRJ200)
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human-Machine Interface; Situational Awareness; Communication Breakdown
Conflict NMAC
Flight Crew Took Evasive Action
Aircraft; Human Factors
Climbing through about 8;000 ft. ATC advised us of VFR traffic at our 1 o'clock; around 3 miles away. It was maneuvering erratically. I immediately saw it. It was performing aerobatic maneuvers. It seemed to me to be rapidly coming towards us from our 1 to 2 o'clock position; so I told the FO (First Officer) to turn left away from it. It was getting very close doing erratic turns; dives and climbs. The FO didn't respond which lead me to believe he didn't see the traffic; so I took the controls and began a sharp climbing left turn. I thought we had cleared it when the FO said he saw it; it was coming back towards us again; at which point I then saw it going straight up; at our altitude; just in front of us. I immediately pulled the aircraft up into a much sharper climb; momentarily at about 30 degrees up. We flew past it within a few seconds. I returned the controls to the FO; took a deep breath; and advised ATC what took place. The aircraft was not in radio contact with ATC.
Captain reported flight crew was forced to take repeated evasive action due to another aircraft maneuvering near them without ATC contact.