What Is Bridge?

A blockchain bridge is a protocol that enables transferring assets between different blockchain networks. Bridges lock tokens on the source chain and mint equivalent tokens on the destination chain. Whale bridge transactions are significant because they reveal cross-chain capital flows — large movements from Ethereum to Arbitrum, for example, may indicate whales chasing better yields or preparing for a new protocol launch. Sonar Tracker monitors bridge-related whale activity across major bridges to surface these cross-chain signals.