To what extent is the flora and fauna on Guadalcanal edible?

Question

At the battle of Guadalcanal,, the initial wave of 11,000 Americans were stranded with something like two weeks' worth of food (five days worth of "landed" rations, nine days worth of captured Japanese rice). Food trickled in with supply convoys over the following days, but the Marines took the standard practice of issuing two thirds of a ration per day. Apparently, the invading Japanese also suffered from food shortages.

What are/were the plants and animals on Guadalcanal, and how suitable were they to be used for food? I would guess that least individual soldiers, though perhaps not the whole force, might have found foraging an attractive option to substitute for the missing one-third ration.

Edit: In constructing this question, I was referring to the first wave of Americans that was "stranded" by the Japanese success in the battle of Savo Island, not the final tally of 50,000-60,000 Americans (and their 20,000-30,000) opponents.

Answer 1

I assume the question around the question is also "could the Marines forage on location"?

You need to keep in mind that the initial stages of the combat around Henderson Field were rather constrained:

• I'd guess about 10-20 KM2 beachhead (maps of it generally have no/unreadable scales)
• that terrain gets frequently bombed and shelled by the Japanese, and "terra-formed" by the Marines, which would flush out prey animals and take down some/many trees.
• the Marines were getting attacked from the East and South, so they would not have been sending out foraging parties outside of their perimeter.

Combined that with T.E.D.'s answer and the number of men (one Marine division + reinforcements, say 11-20K) and living off the land doesn't seem possible. In any case, the Japanese, who were more frugal than Americans, generally had a hard time with food supplies on similar islands.

Answer 2

Tropical environments like Guadalcanal are rather abundant with food, if you know enough to find it. That of course is the key. That generally requires native knowledge, gathered through generations of observation and (often dangerous) trial-and-error.

But there is a limit. Hunting and gathering just doesn't support as many people for the same acreage as cultivation. According to Burger and Fristoe, a reasonable upper bound for the amount of people you could expect a tropical environment to support would be on the order of 100 per 100 km²

Guadalcanal is a 5,320 km² tropical island, which means you could expect it to effectively feed about 5,000 foraging humans, if they spread out evenly over the entire island.

However, the US dropped 60,000 marines there. Foraging could only supply less than a tenth of their needs. In reality what would happen is they'd pick the place clean of useful plants and animals within a week, assuming they'd even be able to identify them. Which they wouldn't, as none of them came from a nearby tropical locale to be familiar with the flora and fauna. It just wouldn't even come close to working.

Additionally, it was not a deserted island. There were in fact tens of thousands of native Melanesian farming people living there.^* Presumably their crops and stores (while they lasted) would be a much better food source to "scavenge", but of course they'd need all that to feed themselves too.

^{* - I can't find an exact number, but today the island's population is over 100,000.}

Answer 3

Buried in https://blog.nationalgeographic.org/2015/03/22/sailing-into-starvation-island-70-years-after-the-end-of-world-war-ii-peace-boat-visits-guadalcanal/ one finds:

“In Japan, Guadalcanal is known as ‘Starvation Island,’ where some 22,000 Japanese and 7000 Americans died in land, sea, and air battles, and of malaria, dysentery and starvation. . .”

Here, https://warfarehistorynetwork.com/2016/10/27/abandoning-the-island-of-death/, you find

“A communiqué from Lt. Gen. Harukichi Hyakutake, the commander of the Japanese Seventeenth Army on Guadalcanal, seemed to bring the matter to a head. On December 23, Hyakutake informed Tokyo of the desperation on Guadalcanal. ‘No food available and we can no longer send out scouts. We can do nothing to withstand the enemy’s offensive. Seventeenth Army now requests permission to break into the enemy’s positions and die an honorable death rather than die of hunger in our own dugouts.’

“The General Staff finally faced the reality of what the men on Guadalcanal were suffering on a daily basis. Hyakutake’s men had drawn up their own method of determining how long a man might survive on Starvation Island:

“He who can rise to his feet—30 days left to live

“He who can sit up—20 days left to live

“He who must urinate while lying down—3 days left to live

“He who cannot speak—2 days left to live

“He who cannot blink his eyes—dead at dawn.”

So, was there edible flora & fauna . . . yes . . . was there edible flora and fauna to support the needs of the US personnel ashore?

No.

No more than to support the needs of the Japanese.

My father was on Guadalcanal in the spring and summer of 1943. He said they never ate anything that was not canned and drank no water that had not been boiled and still dysentery was rampant . . . he spent two weeks in the ACORN hospital with same. Somewhere in my files I have a report detailing the weight loss per pilot in his squadron.