Oceanos mortos, fazendas-fábrica de robôs e cargueiros, dispositivos pessoais de transporte anti-gravidade

Este é um que me deparei em um fórum diferente que ficou sem resposta por um longo tempo. Alguém aqui tem alguma ideia? As informações da postagem original são as seguintes:

There was a sci-fi novel of standard length that dealt with a somewhat dystopic future. There might have been as I remember farm fields (in the UK?) where they tried to eliminate the birds from the hedgerows in order to increase crop yields.

The hero escaped from a factory farm, and somehow gets on a robot freighter headed to sea, probably down the West African coast. There is a description of the desolation of this future time, such as the atomic powered ship that could keep going regardless, but for what purpose? The seas were dead, but traveled by robot or lightly crewed freighters.

He arrives somehow in an area where the very old and rich have found a haven of compounds. Finally, I can remember a scene on the coast of Africa (the continent sure, but perhaps along a desolate sandy coast) where an individual of advanced age was found dead (murdered) drifting along the beach strapped to a refrigerator sized anti-gravity unit.

Além disso:

Set on Earth, probably in the 21st century (a long time in the future for its publ date of 60s), and in a setting where things have gone down the tubes environmentally due to the usual cast of "characters". The English agribusiness, contrary to even 60s UK farm fields, spanned miles and miles, like fields in Kansas or something.

And the protagonist saw the hedgerows made for wind control with fences or nets very high. But birds still survived their planned extermination and hid out in the hedgerows/nets. Due to some intrigue, he has to flee England, and my next recollection is the guy on one of these ocean-going robot ships (robot or staffed by a very few crewmembers) heading away from England on desolate seas.

I remember that the seas were almost lifeless and empty. At some point, he arrives in West Africa, where there are still villas and development for the very rich. These people are so rich that they have every possible aid and assistance to continue to survive and make money, including refrigerator sized anti-grav units that allow them to scud slightly above the ground in their comings and goings. There was some kind of an affair, or dinner party, in one of these villas as the protagonist was trying to find out something about his enemies or his predicament.

It may seem that the world population had crashed, for a number of reasons, so that there were automated production facilities, but no one needed to run them and the very rich who own these enterprises... And then he is out on the beach under a grey sky, and he comes across one of these rich people, dead, floating along the beach, unattended and maybe representative of the situation that the Earth had come to, technologically advanced, but a dead husk. Beyond those three scenes (England, ship, African Coast), I don't recall anything else.

Nota: Estou confiante de que este não é o Half Past Human de T. J. Bass ou a sua sequência. Eu já li isso e a situação social é bem diferente.