As global warming progresses, scientists are observing adjacent discreet habitats beginning to blend together to form larger ecotones.  This push (usually habitats to the south penetrating northward) will likely cause similar species in these habitats, once isolated by the limited overlap between the habitats, begin to come into greater and greater contact with one another.  It is likely that, when genetically possible, these similar species will interbreed, creating hybrids.  

It is well documented that longitude and the rate of global warming are directly proportional such that global warming is accelerating more quickly closer to arctic and antarctic.  This means that the greatest opportunities to study this phenomenon are near the poles. 

The Swan Research Program (SRP) is the world’s leading pioneer in research into Tundra and Trumpeter Swan hybridization.  Our hybridization research is centered around three areas of study:

1. SRP holds an extensive research collection of swans, 15 of which are the only documented hybrids between Trumpeter and Tundra Swans known to exist.  This hybrid collection is extremely valuable in that it can be used to classify these hybrids.  We do this three different ways:  First, we collect DNA from our hybrid collection, as well as our collection of pure Trumpeters and pure Tundras.  Cooperating molecular biologists are working toward isolating genetic markers unique to our hybrids so they can be identified using genetic fingerprints.  Second, because the vocalizations of Tundra and Trumpeter Swans are so different, vocalizations are recorded and analyzed in order to identify hybrids by their calls.  Finally, we have found morphology to be a valuable potential tool to identify hybrids.  Tundra and Trumpeter Swans are very similar in appearance, however slight differences do exist.  It is possible to, with enough baseline data, to use external morphology (appearance) to distinguish between pure birds and hybrids.  Internal morphology, however, is likely to be a more immediately useful tool.  Tundra and Trumpeter Swans have very different trachea structure.  By conducting routine necropsies of deceased birds it is possible to identify them as either a Trumpeter, Tundra, or hybrid.
   
   
2. The information gathered in our research collection is to be supplemented with similar data collection in locations immediately adjacent, but reliably outside of, hybridization zones.  By studying these birds we can gather baseline information on the populations of pure swans that are likely to be directly involved in hybridization, especially as the nearby ecotone advances.  The data would be used as stated above. 
   
   
3. Finally, we will use the data collected in areas 1) and 2) above to survey  hybridization zones in order to determine the extent to which hybridization is occurring in nature.  This will create a baseline survey upon which future surveys of swans in these locations could be compared, and correlated with global warming data.  This will allow us to determine the extent to which global warming is causing hybridization in swans to increase.

Tundra Swan Migration

Native Swan Hybridization and Speciation

Mute Swan Proliferation Control

Trumpeter Swan Restoration