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Direct imaging observations constrain the fraction of stars orbited by gasgiant planets with separations greater than 10 au to about 0.01 only. This iswidely believed to indicate that massive protoplanetary discs rarely fragmenton planetary mass objects. I use numerical simulations of gas clumps embeddedin massive gas discs to show that these observations are consistent with $\sim0.2 - 10$ planetary mass clumps per star being born in young gravitationallyunstable discs. A trio of processes -- rapid clump migration, tidal disruptionand runaway gas accretion -- destroys or transforms all of the simulated clumpsinto other objects, resulting in a desert of gas giants beyond separation ofapproximately 10 au. The cooling rate of the disc controls which of the threeprocesses is dominant. For cooling rates faster than a few local dynamicaltimes, clumps always grow rapidly and become massive brown dwarfs or low massstars. For longer cooling times, post-collapse (high density) planets migrateinward to $\sim 10-20$ au where they open a gap in the disc and then continueto migrate inward much less rapidly. Pre-collapse (low density) planets aretidally disrupted and may leave massive solid cores behind. Gas giant planetsobserved inside the desert, such as those in HR 8799, must have followed anunusual evolutionary path, e.g., their host disc being dispersed in acatastrophic fashion.

A desert of gas giant planets beyond tens of au