Science1 publisher2 min readPublished
GPS tracks from 172 jaguars map 176 corridors linking the species' core habitats
Oxford and University of Southern Denmark researchers mapped 307 jaguar core areas and 176 corridors using GPS data from 172 collared cats. Most predicted movement runs through one South American stronghold, so the land choices that change connectivity lie in thinner links elsewhere.
The Scientist · Science desk
What happened
- The model found major connectivity gaps in Mexico, Central America, Colombia and the Atlantic Forest, where many jaguar populations appear increasingly isolated.
- A second model, connecting 905 protected areas and Indigenous lands, identified 507 potential corridors where conservation could strengthen future links.
- The study appeared in Global Change Biology, with Guilherme Costa Alvarenga of Oxford's WildCRU and Brazil's Mamiraua Institute as first author.
Compiled by The ScientistSomething wrong?How this is made
Why it matters
- decision With most modeled movement already inside one stronghold, the places where protecting land changes connectivity are the narrow links Cushman says habitat conversion could cut.
- constraint Land protected on the strength of a modeled corridor rests on a route surveys have yet to confirm jaguars use, so field checks have to come before the map can justify spending.
- capability A present-day population model set beside a protected-area model lets agencies separate links to defend now from links worth restoring later.
"Previous efforts to map connectivity across the jaguar's range relied largely on expert opinion," said Zaneta Kaszta, a senior author now at the University of Southern Denmark [6][5]. "Our study is based on empirical movement data collected from jaguars across much of their range, allowing us to build a more biologically realistic picture of connectivity." [7]
The advance is in the inputs. The team fitted its model to where 172 collared jaguars actually went, then used it to predict movement across a range that runs from Mexico to northern Argentina [1][2].
Its output is lopsided. One connected landscape across parts of the Amazon, Llanos, Pantanal and Chaco, about 6.5 million square kilometers in 11 countries, ranked as the most important core habitat and held the vast majority of predicted movement density [8]. "Jaguars are in a stronger position than many other large carnivores because they still retain an extensive connected stronghold in South America," said Samuel Cushman, the other senior author [9][5]. "However, our results show that connectivity is far from secure across the species' entire range. Several regions now depend on relatively narrow connections that could be lost if habitat conversion continues." [10]
Simple counting points the same way. If each corridor joins two core areas, tying all 307 into one network would take at least 306 corridors, and the 176 identified fall 130 short [1]. Corridors that branch or thread through several areas would change that sum. On the simple reading, the range breaks into separate clusters, consistent with the isolated populations reported outside the stronghold [11].
The thing this doesn't tell you is whether jaguars travel these routes. The authors say the corridors are modeled pathways, not confirmed movement routes, and that field validation remains necessary [14]. Gene flow, the outcome connectivity is supposed to protect, appears in the study as a concern about those isolated populations [11]. The evidence for isolation is predicted movement [3]. The report does not say how the 172 collars were spread across regions, and the gap regions are where that distribution matters most. I'd trust the broad pattern, one dominant stronghold with thinning links beyond it, well ahead of any single corridor line.
The authors describe the population model and the protected-area model as complementary: the first gives the more realistic picture of present conditions, the second shows where connectivity could be restored or maintained later [13]. "These results provide a framework for prioritizing conservation action across the jaguar's range," Kaszta said [15]. "The maps identify where connectivity appears strongest, where it is most vulnerable, and where future conservation efforts could have the greatest impact." [16]
What to watch
- Field validation of the modeled corridors in Mexico, Central America, Colombia and the Atlantic Forest, where the map shows the thinnest links.
- A regional breakdown of where the 172 collars were deployed, which would show how well the model is anchored in the gap regions.
- Whether governments or conservation groups write any of the 507 protected-area corridors into land-use or protection plans.