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This isn’t a good time to be into charismatic megafauna. Mostly due to habitation destruction the numbers are not going in the right direction. There has been a precipitous decline in the number of lions over the past 20 years. This is probably a good thing for rural Africans, but ideally I envisage a future where most agricultural work will be so high productivity that cities will suck up a lot of this labor (even in the United States economic growth is in a few large urban areas).
But I happily note that this year we seem to have hit the bottom (hopefully) for the number of tigers, World’s wild tiger count rising for first time in a century:
The world’s count of wild tigers roaming forests from Russia to Vietnam has gone up for the first time in more than a century, with some 3,890 counted by conservation groups and national governments in the latest global census, wildlife conservation groups said Monday.
The tally marks a turnaround from the last worldwide estimate in 2010, when the number of tigers in the wild hit an all-time low of about 3,200, according to the World Wildlife Fund and the Global Tiger Forum.India alone holds more than half of them, with 2,226 tigers roaming reserves across the country, from the southern tip of Kerala state to the eastern swamps in West Bengal, according to its last count in 2014.
This is down from ~100,000 in 1900, with declines pretty much every year. Part of this is probably basic economics: the last refuges of tigers are probably the most marginal for farmland. Additionally, economic development and cultural changes are probably having some effect. But the census here is very small. And there are genetic concerns if you look at the sizes for some nations:
Bangladesh, 106; Bhutan, 103; Cambodia, 0; China, more than 7; India, 2,226; Indonesia, 371; Laos, 2; Malaysia, 250; Myanmar, no data available; Nepal, 198; Russia, 433; Thailand, 189; Vietnam, fewer than 5.
For a large mammal a bottleneck of ~100 is probably not a major genetic concern, though some of these populations have been through many decades of small population size. But in terms of sustainability 100 is too close to the edge, so that a low population year might result in some genetic problems, which would result in more problems down the line.
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After reading the news hype about synthetic human genomes, I wonder how long before we have synthetic tiger genomes (or any other rare species).
It seems like we could soon just synthesize some genomes from long dead animals and never have to worry about small populations or inbreeding.
Zoos could be stocked with ancestor clones for breeding.
“I envisage a future where most agricultural work will be so high productivity that cities will suck up a lot of this labor (even in the United States economic growth is in a few large urban areas)”
This is a good descriptor of what is happening in the US. Most people see suburbs being built in cornfields and assume 1) all those people are moving out from central city and 2) we are losing farmland/moving to country. In actuality most rural areas are rapidly losing population, dwindling down to ‘caretaker’ level population. Places, such as West Kansas returned to ‘frontier’ level population density over a decade ago. Also the suburbs as urban refuge settlement pattern worked itself out a couple of decades ago. Now, a lot of movement is rural to suburb or suburb to suburb (with the big exception being Black Flight).
As an example, I can use my ‘homeland’ of NW Missouri. The county I mostly grew up in had a population in the early 20th Century of almost 20,000. This more than halved sometime in the 20’s (curiously, the towns population didn’t change, i.e. it was all rural homesteads). Since the 1970s the population has continuously declined. The demographics donut shaped, i.e. higher than average 50plus population, robust 18 and under population, but very low in the middle. The motivated and the capable leave for college/work and do not return. The majority of the migration pattern is 1.5 hours south to the northern suburbs of Kansas City, which is filled with people from NW Missouri (as certain SW suburbs of Chicago are filled with downstate Illinoisans). The most popular out-state destination is Kansas (essentially still Kansas City), followed by Florida and Texas. Other rural towns that are closer, i.e. more commutable to KC are popular as well. This is all anecdotal based upon my experience, but from subject matter reading it fits the national pattern.
Presumably some of these tiger populations are able to cross frontiers ans bred with tigers from other countries (from India to Nepal, Bhutan or Bangladesh, for example)
I doubt that tigers obey national boundaries. There may be only 100 tigers in Bhutan, but Bhutan is contiguous with Nepal and India. Wouldn’t more relevant populations be for river basins and similar geographic areas?
Sorry Andy. Your comment didn’t load until I posted mine.
The continuing african demographic explosion means that the charismatic african megafauna is in deep trouble.
Even if the mega slums attract a large part of the population the pressure for more resources means that even marginal agricultural lands will be put to use. Not even nature reserves are safe, being constantly invaded by poachers and pastoralists. With many african states ranging between failed to deeply corrupt their defence relies on foreign donors.
This evolution contrasts with the rewilding of Europe and North America that sees growth of forests and protected areas and the reintroduction of species in areas where they went extinct.
It will be heartening in Asia follows in this aspect as well a western model rather than an african one.
yes, some of the pops are continuous. i believe that the bangladesh pop is continuous with a small pop in west bengal along the coast. a bunch of demes of 100 and above are a good way to go right now.