There are two different contexts in which the term "transfer" is used on Kraken.com. Follow this guide to avoid mixing them up when analyzing your history.
Because Kraken Futures is technically a separate platform from Kraken.com:
Withdrawals to Kraken Futures can be distinguished from external withdrawals by the zero value in the Fee column.
Unfortunately there is no way to distinguish deposits from Kraken Futures versus deposits from external sources. You'll need to download your Kraken Futures history from futures.kraken.com and cross-reference it with your Kraken.com ledger.
Before Kraken Futures existed, the Ledger history page and export files have been using the "transfer" transaction type to denote funds passed down from Kraken (e.g. BCH hardfork, XLM airdrop) and funds sent to and from Kraken's OTC desk.
The "transfer" transaction type does not include transfers made to and from your Kraken Futures wallet.