Bald Eagles at Quivira

Adult Bald Eagle roosting

Bald Eagles occur all year at Quivira, and are especially plentiful in winter.  One pair has nested at Quivira since 2009.

Page updated:  13 February 2019

Bald Eagles in Winter

Beginning in late October, migrant Bald Eagles typically begin appearing at Quivira from points north.  They can be seen anywhere at the Refuge, but are particularly fond of Big and Little Salt Marshes, respectively.  A majority are in various stages of juvenile plumages:  mostly brown, with varying amounts of white throughout the plumage.  Bald Eagles take five years to attain full adult plumage (i.e. white head and tail, solid brown body and wings).  Peak numbers usually occur in early-to-mid-December, with upwards of 200 or more possible Refuge-wide.  Numbers of wintering eagles then taper off through the rest of the winter, and by March they are more difficult to find.

A cluster of juvenile Bald Eagles roosting in a tree
A common winter scene at Quivira:  a cluster of juvenile Bald Eagles.


Nesting Bald Eagles

Prior to 2009, the closest known nest to Quivira had been an active pair south of the town of Stafford.  From 2009 onward, there has been active nesting activity by one pair of adults.  Below is the time-line of that nest:


A pair of adult Bald Eagles built a nest in a row of cottonwood trees south of Big Salt Marsh.  This is the South BSM nest, located about 1/3-mile north of the "Artesian Well" pulloff along the NE 140th Street blacktop.  No eggs or young were produced that year.

Quivira Eagle south BSM nest
The nest shortly after first discovered in 2009


Nest activity began being observed in January 2010 at the South BSM site.  By early April, one hatchling could be seen being tended by parents.  By early summer, it was clear that two young birds were in the nest, being tended by parents.  Both birds had fledged by mid-July. Occasionally through the summer and fall an adult or juvenile was seen perched at or near the nest.

Juvenile Bald Eagle probable fledgeling 
Juvenile Bald Eagle photographed in July 2010, shortly after fledging from nest.

Additional note:  this nest was visible from the NE 140th Street blacktop.  During most of the year, a zone around this nest was closed to public entry (complete with signs) to protect the eagles.


Nest activity was again observed beginning in January 2011 at South BSM.  At least one juvenile was observed at the nest in early summer, being tended by parents.  A second juvenile was believed to be in the nest, but was never confirmed.  No birds were in the nest by mid-July, but fledged young were never seen.  Refuge staff believes that the young bird(s) fledged then quickly left the area, along with the adults.  Big Salt Marsh, the nearest large body of water (and food source), was completely dry by mid-summer.


Nest activity at South BSM began in mid-January, with suspected incubation by female a few weeks later.  By early April, neither parent was sitting on the nest, but could be seen coming and going.  Their behavior strongly suggested they were tending young.  One April 14, the St. John Tornado, an F3 storm that originated southwest of St. John, passed directly over the Big Salt Marsh area (in fact, directly over the nest tree itself), inflicting considerable damage to both the nest and the surrounding trees.  It is believed that any young in the nest did not survive.  Miraculously, both adults were accounted for by April 19.  The two adults, and at least one juvenile (possibly one of their previous-year offspring, but no way to prove), were seen sporadically around the Big Salt Marsh area until early July.  No more eagles were seen at Quivira until two adults were observed east of Little Salt Marsh on September 28.  Interestingly, two more (or the same two) were roosting at the nest tree two days later on September 30.
Late-year observations revealed a peak of about 25-30 Bald Eagles in the combined Little and Big Salt Marsh areas (late November), feeding mostly on waterfowl.  By the end of the year, these numbers had dwindled to less than a half dozen.  At least one pair (probably the nesting pair) was in the Big Salt Marsh area during most of the fall.  In addition, a juvenile Golden Eagle was observed sporadically throughout the Refuge from late November onward.


As the year began, a pair of adults continued to be observed in the Big Salt Marsh area.  Sometimes one or both could be seen on or near the South BSM nest, yet another element came into play:  the presence of an additional, similar-sized nest about 3 trees to the west of the original.  This is believed to have originally been a hawk nest, but it has greatly increased in size over the last few months.  Most likely this was simply a "spare", unused eagle nest.  Egg laying at South BSM is thought to have begun in late January or early February, and incubation by the female continued through February and March.  By March 29, activity at the nest (both adults standing on nest) suggested young may have hatched.  Young were seen in the nest in early April.  After a few weeks, it was evident that two young had hatched.  These continued to grow until, on June 14, the birds began flying around and off of the nest.  By June 23, no birds were seen on, or in the vicinity of, the nest.  A juvenile was observed on the east side of Big Salt Marsh on June 26.

 Tornado-damaged south BSM nest in 2012

Eagle nest photographed on April 16, 2012, two days after the tornado.

 Two adult Bald Eagles on south BSM nest 2013

Two adults on nest on 20 January 2013


During December of 2013, a pair of Bald Eagles began building a nest southeast of the Wildlife Drive, just off the northeast corner of Big Salt Marsh.  This nest, Unit 58 Nest, is about 1.5 miles northeast of the old nest at South BSM.  Although the old eagle nest was intact, its use by eagles was almost nil during the same period.  As of the first of the year 2014, a pair of eagles was observed on or near the new nest on a regular basis.  At first the refuge staff was uncertain whether this was the original nesting pair building a new nest, or a new nesting pair.  Ongoing observations revealed it most likely to be the original pair (although impossible to prove), due to the lack of activity at the old nest.  However, a long period of high winds (estimated sustained at 30-40 mph with gusts) on January 16 blew away all but a few sticks of this new nest.  Over the next week, the eagles rebuilt this new nest.  Beginning February 22, an adult was seen sitting on the nest and presumed to be incubating eggs.  Beginning around the end of the first week of April, activity at the nest suggested the eggs may have hatched.  By April 11, refuge staff confirmed that incubating was no longer occurring, and that food being brought in to the nest was being eaten and handled by standing birds (although no young could be seen at that point).

Tragically, high (40+ mph) sustained winds, beginning on Sunday, April 26, destroyed the Unit 58 nest by blowing it completely out of the tree.  The adults were observed alive and well on April 28, but a ground search by refuge staff in the nest tree area revealed not only all of the nest components, but also one dead eaglet.  It is not known whether more than one eaglet was in the nest prior to its destruction.  Throughout the summer, one or two adult eagles were seen sporadically around Quivira, including two adults observed sitting in the Unit 58 nest tree on August 18.


Two adult Bald Eagles on the U58 nest in late 2013
A pair of Bald Eagles on the new nest location (U58) in December 2013

By November 2014, 5-10 Bald Eagles were observed refuge-wide, with a peak of around 50.  In mid-November, adult Bald Eagles were once again seen in both nest trees on occasion.  A few sticks had been added to the Unit 58 Nest, and an adult was seen perched on the old nest on November 12.  By early December, the Unit 58 Nest was apparently rebuilt, with two adults seen at the nest site on December 6.  At least one adult was observed on the South BSM site on more than one occasion during the same period.  During the December 16-17 period, a pair of eagles was seen at each nest site and are believed (although not proven) to be different pairs. 



One or two adults were seen sporadically standing on or near the Unit 58 nest during January and early February, sometimes carrying sticks to the nest.  It wasn't until February 19 that an adult was seen sitting down on the nest, suggesting incubating (nearly matching 2014's first date of 2/22).  This behavior continued consistently through February.  No regular use of the South BSM nest was observed after the beginning of the year.  On or about March 26, hatching is believed to occur, based on the behavior of the adults at the nest (i.e. no longer sitting on nest, but standing on side, sometimes both adults at the same time). 

Tragically, for the second consecutive year, strong winds blew down the nest during the overnight hours of April 2.  Unlike the previous year, these winds were part of a severe storm that did considerable damage to power lines and other structures in a widespread area of south-central Kansas.  Also during 2015, the a large portion of the tree holding the South BSM nest, including the nest itself, collapsed.  There is an old roost nest a few trees to the west of this site, but it has never been used for nesting.

Eagles on the U58 nest in 2015
 Two eagles on the rebuilt U58 nest in mid-January, 2015.


Beginning in late 2015, a pair of Bald Eagles built a nest at yet another location, on the northwest corner of Big Salt Marsh.  This new location is tentatively named the "Y-Road Nest".  No attempt was made to rebuild a nest at the Unit 58 site.  Scattered activity (roosting, nest-building, etc.) was observed at the Y-Road Nest through January and part of February.  Beginning on February 19, an adult eagle was seen sitting down on nest, strongly indicating incubation.  In early April, adults were seen standing on the nest, suggesting young were present.  However, by mid-April the adults had abandoned the nest.  It is possible that, if young birds had been present, they may have either died or been captured by a predator.


Beginning in late 2016, activity was observed in 3 separate locations!  The first, the "Y-Road Nest" was used as a roost by adults and juveniles, but by spring it was not being used as a nest.  However, 2 brand new nests were constructed in late fall:

SWBSM - The Southwest Big Salt Marsh nest was built in a tall cottonwood off the southwest corner of Big Salt Marsh, best visible from the NE 140th Street blacktop about a mile east of the Scenic Overlook.  This location is about a half mile west of (and in the same row of trees as) the South BSM nest location.  By February, one or two adult Bald Eagles were seen fairly regularly on or at the nest, and by the second week of April the actions of an adult there (alternatingly sitting and standing on the nest) suggested hatchlings may be present.  However, by early May no additional activity was observed in or around the nest, and no eagles were seen in its vicinity during June.

Santana - The nest in the Santana Natural Area was built about the same time - late in 2016 - and was getting regular use by adults once completed by the first of the year.  The nest is located about 1.5 miles northwest of Little Salt Marsh.  An adult could be seen incubating through much of late February and March.  On April 13, both adults were seen at the nest, and one was clearly seen feeding at least one hatchling.  After leaves came on the trees, the nest became increasingly difficult to see.  By June 6, one juvenile was seen regularly perched on the edge of the nest.  It was almost fully grown and with brown plumage.  It was not known whether any additional young hatched.

Note:  sometime during the winter of 2016-17, the tree that formerly held the Unit 58 nest collapsed.

Eagle SWBSM nest in April 2017

SWBSM Nest, with adult Bald Eagle attending, in April, 2017

Santana Natural Area nest in March 2017

Santana Nest in March, 2017


At the beginning of the year, both the SWBSM and Santana nests, respectively, showed regular activity.  On February 12, two adults were standing on the Santana nest, and also an adult was observed bringing a branch to the SWBSM nest.  By March 2, an adult was observed sitting down on the Santana nest, strongly suggesting incubation.  This activity was never observed on the SWBSM nest in 2018, and by early April there were no eagles observed around either nest.  What transpired at Santana could only be guessed:  perhaps a nest/egg failure or predation.  The nest at Y-Road Nest (which was never used for nesting) was vacant all year, and by late summer the cottonwood tree supporting it appeared to have died.


By mid-January adult eagles were observed with regularity around both the Santana and SWBSM nests.  On January 24, two adults were seen moving sticks around on the Santana nest, and one adult was observed standing on SWBSM nest.  On February 13, an adult was seen sitting down on Santana nest, strongly suggesting incubating.  The same day, an adult was observed bringing sticks to the SWBSM nest while another looked on from the tree.  By March 25, both Santana and SWBSM nests each had an adult on nest, incubating.