The S&P/ASX 200 Index (ASX: XJO) has followed Wall Street's lead and is pushing higher on Monday. At the time of writing, the benchmark index is up 0.2% to 8,265.1 points.

Four ASX shares that have failed to follow the market higher today are listed below. Here's why they are falling:

Bellevue Gold Ltd (ASX: BGL)

The Bellevue Gold share price is down 9% to $1.04. Investors have been selling this gold miner's shares on Monday after it downgraded its production guidance. Management has revised its full year gold production guidance range to 150,000 ounces to 165,000 ounces. This compares to its original guidance range of 165,000 ounces to 180,000 ounces for FY 2025. The company blamed its underperformance on lower grade production as the mine sequence progressed through the outer edges of the orebody moving towards the higher-grade core.

BHP Group Ltd (ASX: BHP)

The BHP Group share price is down almost 2% to $39.06. This follows broad weakness in the mining sector on Monday. According to CommSec, iron ore futures slipped 1.2% to US$99.44 per tonne on Friday. This was driven by some traders liquidating long positions on faltering demand after most steelmakers in China completed pre-holiday restocking of feedstocks. This meant that iron ore fell for a third straight week and was down 4.3% for the period.

Brainchip Holdings Ltd (ASX: BRN)

The Brainchip share price is down 8% to 38 cents. This may have been driven by profit taking after some strong gains in recent weeks. For example, this semiconductor company's shares are up almost 70% since this time last month despite today's pullback. In addition, Brainchip issued 204,813 shares to one of its directors on Monday after they vested their performance rights.

Peninsula Energy Ltd (ASX: PEN)

The Peninsula Energy share price is down 5.5% to $1.39. This is despite the uranium developer announcing its new managing director and CEO this morning. Peninsula Energy has named George Bauk as its new leaders. He will commence in the role on 20 January. Bauk said: "I am extremely pleased to be joining the Peninsula team at such an exciting and pivotal time for the Company. I want to acknowledge the outstanding work of Wayne in bringing the Lance Project back into production and setting a solid foundation for its future success. I look forward to collaborating with him in his advisory role as we build on this achievement."