So, don't sell to them instead, hold patiently and in matter of time depending on your goals and assets values, you could imitate them (whalers) or could even be one in the future.
As far as someone wants to make a profit from Bitcoin investment, they must learn how to be patient enough to hold Bitcoin for a long period of time until they can make a reasonable profit. However, the truth is that one day, someone must sell because no one can hold Bitcoin forever. Another thing to consider is that if whales want to make many people sell, they can manipulate the market. They might start buying Bitcoin aggressively, pumping up its price due to their pressure of buying. When the price increases, people with small capital might begin to buy more.
After a while, when the whales see that they have inflated the price, they will sell a large portion of their Bitcoin, causing the price to drop. At that point, people with small capital will begin to panic and start selling at a low price. The whales might then exit the market temporarily and return later to buy Bitcoin at a cheaper price.The key takeaway is that if someone notices that Bitcoin is at a great price, they can sell a portion, such as 30%, and buy back when the market is down again if he don't have waht they will use the money for.