What academic fields have high demand, but low supply?

I was reading the Wikipedia article "Decline in insect populations," and the last paragraph surprised me. A major issue with quantifying the rate of extinction and population declines in insect species is that there aren't remotely enough entomologists and taxonomists for the task, as their ranks have decreased for decades:

One reason that studies into the decline are limited is that entomology and taxonomy are themselves in decline. At the 2019 Entomology Congress, leading entomologist Jürgen Gross said that "We are ourselves an endangered species" while Wolfgang Wägele – an expert in systematic zoology – said that "in the universities we have lost nearly all experts". In 2016, Jürgen Deckert of Berlin Natural History Museum commented that while around 30,000 insect species are known to inhabit Central Europe, there are "only a few specialists" dedicated to the region, and even they often do monitoring as a side job. General biology courses in college give less attention to insects, and the number of biologists specialising in entomology is decreasing as specialities such as genetics expand. In addition, studies investigating the decline tend to be done by collecting insects and killing them in traps, which poses an ethical problem for conservationists.

Looking at some of the citations and more recent articles, it seems the demand for these experts has increased significantly, but there aren't enough students in those fields to replace them when they retire, in part due to a chronic lack of funding.

I've been strongly considering going back to university for the past several years, but other than the cost and other personal issues, the thing keeping me from it is that I really want to do academic work—research, writing papers, teaching, etc.—and academic jobs in the fields I've looked into the most are extremely scarce and highly competitive. Therefore, the prospect of an academic field in high demand, but with a low supply of qualified workers, piques my interest. I usually see that with laborious trade jobs and niche industries, not branches of natural or social science.

Do any of you work in or know of an academic field or subfield where this applies? Rather than an intensely competitive market, does your discipline have so few students or experts that finding someone qualified is difficult? Would you recommend people consider that when choosing a career, or are there other factors (lack of funding, very specific requirements, etc.) that make that choice unwise?