FWS Assistant Field Supervisor Joyce Collins marks least tern eggs for transfer. USFWS photo.

FWS Assistant Field Supervisor Joyce Collins talks with local media regarding closure of Odd Fellow Road. USFWS Photo by Matt Mangan.

FWS biologist Matt Mangan monitors least tern nesting on Odd Fellow Road. USFWS Photo by Karen Mangan.

Chicks from nest on Odd Fellow Road. Younger chick is from egg transferred from Swan Pond Road. Photo by Scott Ballard, Illinois Dept. of Natural Resources.

Endangered least terns nesting on Swan Pond Road. USFWS Photo by John Magera.

Endangered least tern nesting site on Swan Pond Road, Jackson County, Illinois. USFWS Photo by John Magera.

 Each year small numbers (several hundred) of endangered least terns migrate north to the Middle Mississippi River to nest on traditional nesting islands, such as Bumguard Island, Brown's Bar and Marquette Island.  However, flooding along the Middle Mississippi River began in March this year and continued well into July.  Within the levee districts, extensive flooding also occurred due to massive watershed rain events and an inability to pump the water out of the levee district.  Consequently, large amounts of agricultural lands (hundreds of acres in places) were also flooded.  As least terns arrived in the area, finding suitable nesting sites proved challenging.

In late May 2008, staff from the Marion, Illinois Ecological Services Sub-Office was contacted by staff from the Middle Mississippi River National Wildlife Refuge regarding the sighting of least terns along Swan Pond Road, located in Fountain Bluff Township, near the community of Jacob, in Jackson County, Illinois.  On June 5, MISO staff met with Refuge staff to ascertain whether least terns were nesting on the road.  During the field visit, three adult least terns were seen, as well as several nest scrapes, indicating courting and possibly nesting behavior.  MISO and Refuge staff agreed to continue to monitor the situation.  From June 5 to June 18, four nests with eggs were located on the road.  Additionally by June 18, Refuge staff had found three dead adult least terns along the road.  It was suspected that these birds were killed by the road traffic.  Consequently, on June 19, MISO staff, along with Refuge and Law Enforcement staff, met with the Fountain Bluff Township Road Commissioner and Jackson County Highway Engineer to discuss the situation with least terns nesting on the road.  During that meeting, Service staff confirmed the death of an additional adult least tern and the destruction of one nest due to crushing by vehicle traffic.  The road commissioner finally agreed to allow closure of the road and posting of signs to prevent disturbance of the nesting birds.  Service staff agreed to closely monitor the nesting birds in order to ensure the road could be reopened as soon as possible.

During the week following the road closure, six new nests with eggs were located.  On June 28, nine additional nests were located, bringing the total nests being monitored to 18.  Approximately, 40 adult least terns were utilizing the area.  However, during monitoring on July 6, only one active nest with two eggs and one abandoned nest with two eggs were located.  The remaining nests were destroyed and all the remaining eggs were missing.  No evidence of predation was seen.

The closure of Swan Pond Road generated some media interest which resulted in MISO staff being contacted regarding additional least tern nesting sites in the area.  On July 2, MISO staff noted approximately 50 adult least terns on Odd Fellow Road, located near the community of Jacob, Jackson County, Illinois.  This road had been continuously closed due to high water, but similar to Swan Pond Road, a middle section of the road was elevated out of water and contained small gravel providing suitable nesting substrate for least terns.  On July 16, MISO staff counted 46 nests with 84 eggs at this location.  Although the road remained closed due to flooding, water levels were receding by this time.  Consequently, MISO staff met with the Fountain Bluff Township Road Commissioner and Jackson County Highway Engineer to discuss closure of this road.  The road commissioner reluctantly agreed to allow the road closure, but requested reopening of Swan Pond Road since only one active nest remained at that site.  MISO staff indicated that this would not likely be possible as the traffic would impair the nesting behavior of the least terns.  However, following the Odd Fellow Road closure, MISO staff discussed with Rock Island Field Office and Regional Office staff the idea of an experimental approach to address the situation.  This experiment would allow the removal of the two remaining eggs on Swan Pond Road to the active nests of other least terns nesting on Odd Fellow Road.  MISO staff would monitor to see if the least terns on Odd Fellow Road would "adopt" or reject the extra egg in their nests and/or continue with normal incubation activities.  The adult least terns accepted the new eggs without incident. 

Following transference of the eggs from Swan Pond Road to Odd Fellow Road, the adult least terns on Swan Pond Road were hazed away to ensure they would not be killed by vehicle traffic.  Swan Pond Road was reopened to normal traffic on July 18.

During monitoring of nesting on Odd Fellow Road on July 22, MISO and Illinois Department of Natural Resources staff noted 46 nests containing 68 eggs and located 15 least tern chicks.  One of the nests in which an egg from Swan Pond Road was relocated had three chicks which had hatched.  One of these chicks was from the adopted egg.  This proved the success of the experimental approach of moving eggs from one active nest to another.  However, the success of such an approach depends upon closely monitoring nesting activity and determining the beginning of incubation of the eggs. 

Unfortunately, during monitoring on July 25th, only six eggs and no chicks were located.  Several egg fragments were found, along with coyote scat.  Additionally, several dozen great egrets had congregated in the area.  A couple of weeks prior, the levee and drainage district had opened the levee drainage pipes in order to drain water from the levee district.  The result was that most of the water covering Odd Fellow Road receded, allowing greater opportunity for exposure of nests to predation.  MISO staff continued to monitor the site until August 1 when no adults were seen in the area.  The six remaining eggs were collected for contaminants analysis and the road was reopened to traffic.

While the outcome of least tern nesting on Swan Pond Road and Odd Fellow Road was disappointing, several important lessons and opportunities were noted:

1.  Once Swan Pond Road was closed, no additional adult least terns were killed in that area.

2.  The Swan Pond Road closure provided the opportunity for two outreach events, one of which specifically targeted the children in the community of Jacob.  On June 28, MISO and Middle Mississippi River NWR staff hosted an educational event to foster understanding for least tern nesting within the community.  Forty-two individuals attended the event, including 20 children age 12 and under.  This was considered hugely successful.  Additionally, on July 9, MISO staff met with 20 students from Rend Lake Community College to discuss the least tern situation at Swan Pond Road.

3.  The experiment of moving viable eggs from one nest to another active nest proved successful.  This information may prove useful in the future to protect least terns nesting in other unsuitable areas.

4.  The areas chosen for least tern nesting indicated that the most critical factor for selecting nest sites is the presence of large expanses of water around the potential nesting area.  The expanse of water is critical to protecting nests from predators and providing foraging habitat near the nest site.  This information will be used during habitat restoration planning in the Middle Mississippi River to develop projects that should have a greater opportunity for success.

5.  Several Service offices/programs contributed time and resources to assist MISO staff with addressing the issues of least tern nesting on Swan Pond Road and Odd Fellow Road.  This includes the Middle Mississippi River National Wildlife Refuge; Springfield, Illinois Law Enforcement Office; Crab Orchard National Wildlife Refuge; Carterville National Fish and Wildlife Conservation Office; and Cypress Creek National Wildlife Refuge.  Additionally, local Illinois Department of Natural Resources staff assisted with monitoring.

6. Six least tern eggs will be submitted for contaminants analysis.

7. Water samples were collected along Swan Pond Road and submitted for contaminants analysis.  These results are pending.