The attendance at your arena depends on several factors, the away team is an important one.
Your attendance was 8877 against I.C.B.C., conference leader (5W, 0L) and 8179 against Miracle Dream (3W, 5L). If you didn't change your tickets prices, the difference in quality between your last opponents is probably the main reason why your arena attendance went down a bit. 700 isn't a huge drop, for your arena size, you can expect to see 1.5K drops in attendance.
Did you change your prices ?
Do you know if Bald Eagle has changed his tickets prices ?
His attendance was 7725 against BC Lorenzo (8th, 1W, 5L) and 9088 against Train Rockets (7th, 2W, 6L).
He has lost his last league game before BC Lorenzo but won it before Train Rockets, winning your last league game is a very important factor for drawing audience to your next game.
And it's only a guess but he has probably lowered his prices.
Last season, you were promoted as a league champion. As a result, you had 5 balls all season long at 'I am pleased with the team's performance last season' on your fan survey. It has helped filling up nicely your arena last season giving you a bonus on your attendance, I think the bonus is usually estimated around 15%. I believe it's a very important factor.
This season, I guess you have between 2.5 and 3.5 balls as response to that statement depending on the survey. If you don't have much better results than last season, your attendance lowers, the fan's excitement after your promotion has fainted, now it's again routine regular season games bla bla bla bla... except when I.C.B.C. comes around ^^ whoopa everyone wants to see them and their stars ;)
People don't come at your arena only for your team ;p Your die-hard fans come for you even in hard times but they are only 2k+, they are a small part of the attendance.