Ecology Shifting Northward

Ecology Shifting Northward

New research by the University of Nebraska-Lincoln shows the effect of climate change. The team analyzed the data of bird’s distribution of the last 50 years in the USA. They found that the whole ecosystem is moving towards the north in the Great Plains. 

The previously available northernmost ecosystem pushed its boundary to 365 miles north. The starting point that means the southernmost boundary changed its position. In comparison to the baseline of 1970, this boundary has moved 160 miles northward. 

The result can develop an “Early Warning” system. It is a process to aware of the land managers to be prepared for any kind of ecosystem shift or collapse. This early warning will allow them to foster changing conditions in our climate. It is better than reaction according to the researchers. 

As long siren warns about any natural disaster like a tornado, early warning alerts us about the greater threats of ecological changes. Ecologists thought for a long time that external pressures, climate changes, invasive species have an influence on the ecosystems. The effects are idiosyncratic and unpredictable most often.  

But this idea has been proved wrong by this study. The result of the research was published in the journal Nature Climate Change on June 24. They were able to measure the spatial components that were responsible for the change for the first time. They found that the ecological responses are ordered and can be estimated previously by monitoring the pattern of responses.   

"If we can work toward prevention (of changes), we're going to save ourselves so much money and time," said Caleb Roberts, lead author and postdoctoral researcher at Nebraska. "We won't have to worry about specific endangered species, perhaps, because we will be protecting the system they require."

The North American Breeding Bird Survey led a Geological Survey program in order to estimate bird population. They included 400 hundred bird species living in 250 miles wide area from Texas to North Dakota. They gathered the data for 46 years and this data was used by the researchers to conclude their experiment. 

In the next step, the team categorized the bird species into several groups according to their body mass. Then they tried to find out if there was any gap in their distribution or not. As the DNA structure shows the condition of a body, the gap structure of the birds shows their present condition in that ecosystem and it is quoted by Craig Allen, a co-author. This deeper observation paved them the way to have a hint about the ending point of an ecosystem and the starting point of the other.  

They analyzed the 46 years long body-mass signatures and geographic movement of the birds. They also measured the amount and speed of their shift from their current space to the north. 

"All (these breaks) are saying is that there are a lot of animals with the small body size; then there's a gap with nothing in this middle body size; then you have another group and another group," said Allen, director of the university's Center for Resilience in Working Agricultural Landscapes. "And since these reflect the domains of scale in an ecosystem, it's like a signature -- the DNA -- of a given ecosystem."

The rate of shifting in the northernmost boundary is frequent than that of the southernmost counterpart. This term is now known as Arctic amplification. Climate change is showing its might as it has forced the birds to move their habitat although slightly. Some other changing drivers that cause their shifting are wildfire trends, energy development; agricultural land conversion; and urbanization. 

"Like most things in ecology, (these shifts) likely have multiple causations," Allen said. "And I think it's fairly intractable to try to separate, say, tree invasion from climate change, because it has to do with fire but also with changing the climate. All of these things are highly related."

According to Robert, the grassland ecosystem is the most threatened one.  He said, "Those are all things we can do and use the early warning to say, 'We're coming to the edge of this grassland's resilience. It's about to collapse, especially in our area. What can we do to stop that?' That's the kind of power this tool would have." He again said. "You don't have to wait until it gets to you. You can see it coming and act pre-emptively."

Allen warns the land managers not to wait too long for the problems to be out of control. If it becomes too acute, its consequences cannot be avoided. As the team has found this type of ecological change in the north, they are willing to expand their researches on the east and west as well. They will consider forestlands and mountain ranges then. 

Dirac Twi dwell said, "We are working closely with a long list of partners to understand how to navigate these types of transitions and increase the performance of conservation investments. Large-scale transitions should not be underestimated. Restoring what has been lost has proven extraordinarily difficult when the challenge spans large geographic regions."