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Swan Death Necropsy

January 31st, 2015 | Posted by LadyNerkle1 in Swans Death Necropsy - (Comments Off on Swan Death Necropsy)


Swan Death Necropsy
OH NO ! ! WHAT Happened ! ! WHAT Happened ! !

This is a Topic that is also Important.. but, not the Fun Part of what I do…

As Sad as the Loss of a Pet/Swan will be..
This is Information Good to Know…before it Occurs.

This is a Topic Page I am Organizing the Best I Can..
So Many things keep Changing.. so, I will NOT have all Details..
Every State has a Department of Agriculture..
with an Animal Pathology Laboratory.
Each State’s Department of Agriculture will have their Own
Services, Policies and Programs to Help you.

When I get a Call that a Beloved Swan has Died..
I Hear the Disbelief and Anguish in the Person’s Voice..
Swan Death Necropsy

When their Swan has been Taken/Killed by a Predator..
They know what Happened.. a Violent End to their Beautiful, Pet Swan..

BUT, when their Swan is Found Unexpected.. without a Mark..
It is Bewildering.. So many Questions.. “WHAT could have Caused this” ??
Swan Death Necropsy

There are SO MANY Possibilities…

Was it Something they Swallowed..??  Something they Ate..??
Swan Death Necropsy

Was it Something in the Feed Mix..???   Is it Contaminated..??   Mold..??
Swan Death Necropsy

Did the Swan Eat anything with Mold..??  Like Old Bread..??
Did the Swan Inhale a Fungi or Mold from Dusty Bedding..??
The Young Swan below Died of an Advanced Aspergillosis Infection.
Swan Death Necropsy

We Rescued this Black Australian Cob..  He was Starving due to Food Competition.
After Weeks of Slow Progress.. he Failed.. Several of his Internal Organs
had been Damaged from Lack of Nutrients..   ( So Sad.. he was a Nice Swan.)
Swan Death Necropsy

Did the Swan have a Parasite Infestation..??
Did the Swan Drink Pond Water Infected by Wild Waterfowl..??
Many Waterfowl Diseases are Spread during Migration Season..
Swan Death Necropsy

Did the Swan Succumb to a Mosquito Borne Disease..??
The Tiny Cygnet below had Necrotic Encephalitis from a Mosquito Bite.
Swan Death Necropsy
Has the Pond Water become Unhealthy.. Stagnant..??
When the Water does not Refresh..  Bacteria Counts get TOO High..
Swan Death Necropsy

Did a Venomous Snake Bite Kill your Swan..??
Swan Death Necropsy

Did a Toxic Substance Drain into the Swans’ Environment..??
Swan Death Necropsy

Did a Bumble Sore become Septic..???
Swan Death Necropsy

Did the Swan Consume a Pest Poison like Rat Poison..??
The Cob below.. Died Suddenly… The Owner Feared he had Eaten Rat Poison
that was Tucked under the Feeder..  Testing Concluded, he Died of Avian Cholera.
Likely from the Rodent Saliva Contaminating his Feed..   Not the Poison..
Swan Death Necropsy

Did the Swan have an Under Chin Impaction Preventing Eating..??
Swan Death Necropsy

Did the Swan have a Birth Defect.. that became Fatal as it Grew..???
Swan Death Necropsy

The Cygnet below had a Neck Deformity that made Eating VERY Difficult.
Swan Death Necropsy

Did the Swan Fly..??? Injury from a Difficult Landing..??
Swan Death Necropsy

Did the Swan Freeze – Frozen Out from any Open Liquid Water..??
Swan Death Necropsy

Was there FOUL Play.. Human Vandalism..??
BB Gun Pellets..??  Blunt Force Trauma..??
Swan Death Necropsy

Was it Possibly Electrocution..?? Electrical Leakage..??
Did a Faulty Electrical Cable in the Water Shock-Electrocute the Swan..??

Common with Waterfowl that Fly > Power-Line Collisions.
Swan Death Necropsy
Electricity Sources, Primarily Overhead Power Lines.
Swan Death Necropsy
Tissues are Damaged Directly and Via Burns.
Electrocution may cause Apnoea ( Cessation of Respiration )
and Ventricular Fibrillation ( Irregular Heart Beat )
Death may Not Occur Immediately..
but, Resulting from Internal Tissue Damage.. Days or Weeks Later.

A Lightening Strike..??    > Yes, this is Possible..
Swan Death Necropsy

Electro-Coagulation Injury or Limb Paralysis.
Lightning will Spreads in Water and Living Creature in the
Lightning-Charged Water may be Physically Damaged or Killed.

ETC. ????? Questions..?? Questions..??  Guessing, Guessing..

If you want to Know and NOT just Guess..
This Information will Help you Learn.
You can Submit your Swan for Necropsy.
So you are NOT Wondering, Wondering with No Answer.


Your Immediate Action will Determine whether
you will have a Chance to have your Dear Swan Evaluated..

> > > When you find your Swan Deceased:
> > > DO NOT TOUCH the Body with your HANDS.
Swan Death Necropsy

> > > FIRST: Look at the Body for Signs of Trauma
-Blood – Feathers Torn Out – Body Parts Missing..

If the Swan was Killed by a Predator make some Notes of the Damage
to the Body.. Where it was found. Take a Photo or Two..
Anything that might be of help to Identify what Predator may have Killed
your Waterfowl/Swan. This is Gruesome, but this may Help ID the Predator..

Doing a Necropsy will not be of much Help
if your Swan/Waterfowl was killed by a Predator.
Swan Death Necropsy

If you have any Pet/Swan that Dies from an Animal Attack..
> > > Protect Yourself.. Hands, Arms, Eyes, etc.

Your Swan/Waterfowl may not have had any Diseases, but the Animal
that Killed it will have Bitten and left Saliva all over the Carcass..

Mammal Saliva MAY CARRY Rabies or other Contact Diseases.
Swans do not get Rabies.. In General Birds do not..

If you have ANY Pet that is Attack be sure to Protect Yourself..

> > > Carefully WITHOUT Touching the Body,
Put the Body into a Bag/Double Bag-Secure for Disposal.
> > > WASH your Hand WELL after Bagging the Body.
Swan Death Necropsy

Once you have your Observation Notes:

If your Swan/Waterfowl Dies Unexpectedly.. Suddenly…
or after a Period of Declining Health – Weakness – Wasting.
Swan Death Necropsy

Did you Notice any Different Behavior in the Last Week or So..??
Swan Death Necropsy

IF you can not Determine the Cause of the Death..
and you want to Submit for a Necropsy.. Evaluation..

To Preserve Deceased Swan/Waterfowl for a Necropsy:

> > > Immediately, DO NOT Touch the Body with Bare Hands.

Swan Death Necropsy

> > > PROTECT Yourself..
         – Wear Gloves & Protective Gear..Protect your EYEs ! !
– No Safe Gloves > Use a Barrier such as an Inverted Plastic Bag.

> > > CAREFULLY Put Deceased Swan in Thick Plastic Trash Bag.
– Swans are Large and 2 Large Garbage Bags will be Needed.
– Secure Opening.. then Place the Wrapped Body in Second Bag.
> > > Tape a Note on inside Bag
– with Your Name, Phone, Birds Name, Date.
> > > Also Tape the Same Information on the Outside Bag.

> > Refrigerate until you Contact your State Animal Path Lab..
– OR Place in a Cool Place.  A Very Large Ice Chest with Ice/Cold Packs.
Swan Death Necropsy

> > > WASH your Hand WELL after Bagging the Body ! !

> > > Always Call the State Animal Pathology Lab for Instructions.
You will be asked Questions and to fill-out a Form
with General information about the Bird’s Age, Living Environment,
Feed, other Animals on your Property. Any Signs of Illness ??
A History to help the Lab know where to focus their Immediate Attention.
The Submission Forms are Usually Available OnLine.. or by EMail..

> > > If you Read the Link for the Avian Influenza Information..

> > > If this is a Possible Cause of Death.. Do NOT Bury..
> > > Until you Speak with the State Pathology Lab.
Swan Death Necropsy

A Person from the State Path Lab Staff “may” Come to YOU..
You may not Need to take your Swan to them..
They will Collect Swab Samples for the Testing.
> > > Keep Body in a Cool, Dry Place in Large Plastic Bags..

Check on your Other Swan, Waterfowl.. Make some Notes..

> > > NEXT- Concern “HOW is your Remaining Swan..?? ” ???
Maybe Both Swans are Affected.. All Birds Hide any Illness
or Impairment until they are in Real Trouble.
Learning what Caused the First Swan’s Death may Save the Other..
Swan Death Necropsy

When I hear Folks say, the Old Wives Tale, which I will Loosely Quote:
> > > “If a Swan’s Mate Dies, the other will Die of a Broken Heart.”

Personally, I Believe… the Remaining Swan may have been Ill…
Swan Death Necropsy

And if you Learn what Caused the first Swan to Die..
You will have a Chance to Save the Remaining Swan..
Example: Parasite Infestations will Affect both…
Prompt Treatment will Help.

When a Bonded Pair have been Together for a Number of Seasons..
They are Bewildered when their Mate-Companion is Gone.
Swan Death Necropsy

Swans depend on each other for their Common Safety.
Each watching for any Sign of Danger. They take Turns Sleeping..
Swan Death Necropsy

WATCH for your Remaining Swan to go Wandering to Look for their Mate..
Walk them BACK to their Ponds..
Swan Death Necropsy

A Lone Swan feels more Vulnerable and you will Experience
a more Cautious Behavior.
They are more Guarded. They go into a Survival Mode.
Not wanting to come close to You now is Normal.
Sleeping at Night is Less Safe.. They will Nap more in the Day Time..
Swan Death Necropsy

You can Help your Swan.. by Spending Quiet Time near the Pond.
Make Extra Visits each Day, even 5 Minute Visits..
Take some Lettuce or Treats. Talk Quietly or Work Nearby.
Swan Death Necropsy
Swans do Grieve, become Subdued.. Quiet..
They are Different.. There is a Sadness about them.

A Lone Swan is a Lonely Swan

Your Company will be Comforting during this Lonely Time..
It may take Several Days or Weeks for Remaining Swan
to adapt to being Alone..
Swan Death Necropsy

Healthy Swans Adjust.. But, they are always Happier with another..
Given a Few Weeks to Mourn, Swans will Accept a New Companion/Mate.
Swan Death Necropsy

Then after that Time.. Introducing a New Swan is OK..
They will Accept a New Companion much Easier..


SWANs are Indicator-Sentinel Species.
Biological Species that can Help Monitor the Environment.
Swan Death Necropsy

To Study Animal Indicator-Sentinel Species Gathers Important Information
for a Given Region.  Especially around Annual Migration Seasons.
Swan Death Necropsy

An Indicator of Disease Outbreak, Pollution, Species Competition
or Effects of Climate Change.
Indicator Species are an Early Warning to Monitoring Biologists.

SEE Additional Information at the End of this Topic Page..


Your STATE should have a Department of Agriculture.
You will be Contacting their Animal Pathology Laboratory.
Ask to Speak with the Poultry Inspector or Avian Specialist.
Check their Locations and Phone Numbers
– being Prepared is a Good Plan.
Your Depart. of Ag. can be helpful with Pond Environment Problems.


I was a Hospital Laboratory Technologist during my Working Days..
It is an Environment that Looks for Answers when People are Sick or Injured.
Diagnosising and Monitoring Treatment or What Happened..??
If a Person Dies Suddenly/UnExpectedly, an Autopsy is Done.

With our Furry or Feathered Pets-Livestock.. a Necropsy is Done.
Refers to a Post-Mortem Examination on an Animal Species.

We have had many Dear Swans Necropsied over the Years..
Always a Surprise when the Reports were Finished.

You will have Help learning the Cause of Death
and will be able to Consult with the Pathology Lab Specialists
and get Advice from your State’s Department of Agriculture..
Some Problems can be Very Difficult to Resolve without their Help.
The Department of Agriculture Contacts are there to help you..


Most Department of Agriculture Pathology Labs.
Basic Necropsy Services, Schedule and Procedures..

> > > CALL them FIRST – You will be Interviewed..
Follow Instructions If you Submit a Swan for Evaluation:

This is what may be Checked during the Necropsy.

Basic General History of the Swan
> > > You will be asked Questions when you call.

Avian Pathology – Necropsy – Interpretation
Gross Visual Observations – General Results
Preliminary Diagnosis – Comments

Depending on the Gross Morphology.. – Visual Findings..
> > > Samples that might be Collected for Testing.

Swan Death Necropsy

HistoPathology – Biopsy Slides – Micro Tissue Exam
Molecular Biology Trachea – Various Infectious Viruses
Microbiology – Aerobic and Anaerobic Cultures

Test: Microbiology Aerobic Culture ( Where Blood Flows. )
*** This is to ID Bacteria that live in Oxygen Rich Environment..

Test: Microbiology Anaerobic Culture ( Oxygen Poor Wounds. )
*** This if for Infected Bites, Abscesses and Gangrene.
Many Anaerobic Bacteria produce Enzymes that Destroy Tissue
or sometimes release Potent Toxins.
Example: Assorted Clostridium Strains Untreated are Often Fatal..
C. tetani ( Tetanus) C. Botulinum ( Botulism )
Swan Death Necropsy

Test: Microbiology Antibiotic Susceptibility ( MIC )
*** This is to ID Bacteria Sensitivity to various Antibiotics
that should successfully Treat any Bacteria Identified
as the Primary cause of Illness.

Swabs of Liver – Brain – Intestine Tissue Pool – Salmonella Culture
Avian Serology Testing – Virology
Parasitology – Exam for Parasites
Mycotoxicology – Fungus Identification

They may Check for Insecticide or Herbicide Toxicity, other types of Poisons,
Heavy Metal Toxicity.. depending on the History you Provide.
Swan Death Necropsy

The Young Female below Died Suddenly.. NO Warning..
She had Ingested a Small Piece of Iron that was Dissolving in her Gizzard.
The Iron Toxicity had Severely Damaged her Heart, Liver and Kidneys.
Swan Death Necropsy


You will get the Following Reports by U.S. Mail and/or EMail:

#1 Preliminary Report Same Day Report.. ( Visual Impressions. )
Occasionally within a few Days of Submission.

#2 Interim Report .. 3-10 Days.. with Some Sample Results-Findings.

#3 The Final Report.. Generally 3-6 Weeks..
When ALL the Tests Preformed have been Completed.
This will have the Conclusion.. a Summary of All the Findings.

I have Sadly Learned many things over the Years..
How Many Unexpected Things can Happen..

Submitting your Swan/Cygnet for a Necropy will have the Benefit of Learning..

If there is No Clear Reason for a Swan’s Death, I want to know,
so I have a chance to Correct a Problem that I am not aware of.
Valuable for Future Care – Knowing what Happened rather then just Guessing.

Considering what you may have Paid to Adopt your Swan/s.
Spending $50.00-$100.00 to learn what Happened may save the Life
of other Swans and Waterfowl in your Care.

” You become Responsible, Forever, for what you have Tamed.”
– Antoine de Saint-Exupery.
Swan Death Necropsy

I am Always Sad to hear this Type of News..
I Appreciate your Heart Ache..
Swan Death Necropsy
It is Emotionally Traumatic when Something Happens
so Suddenly.. or Unexplained.
Swans become a Part of our Lives..
I Understand how Haunting their Memory is.. We have been there..
A Pond, Lake or River Never Looks the Same when Swans are Gone.
Swan Death Necropsy
…. Wish I could Say something Comforting..
Swan Death Necropsy


Compiled by Linda M.Sweger February 2024


SIDE NOTE – The Value of Testing Wild Swans..

Because of their Limited Diet in the Wild Environment, Mute Swans
are a Sentinel Species, concentrating Contaminants in their Livers
and Revealing the Presence of Chemical Toxicities in Fresh Water.
Rather than Eliminating Swans, we should Pay Attention to their Struggle
to Survive and What it can Tell us about the State of our Wild Areas.
Swan Death Necropsy

TESTING the Wild Swans:  2017 in Michigan:
A Health and Disease Surveillance Project was being conducted
in coordination with the Management of Mute Swans, which
received Funding through a U.S. Environmental Protection Agency’s
(EPA) Great Lakes Restoration Initiative Grant and a Cooperative Service
Agreement with the Michigan Department of Natural Resources.

The Avian Health and Disease Program provided Funding for Health
Monitoring and Disease Surveillance Activities.
Samples collected from Mute Swans are being tested for:
Avian Influenza, Newcastle Disease Virus, Avian Cholera,
Duck Viral Enteritis, Intestinal Parasites, Toxoplasmosis,
Eastern Equine Encephalitis, West Nile Virus, LaCrosse Encephalitis.
Environmental Contaminants, Toxic Herbicides and Pesticides.

Results will help establish Avian Health Baselines that can then be
monitored periodically, identify existing and emerging Avian Health Risks,
provide for the early detection of any Introduced Diseases,
and provide guidance for Population Management.
Swan Death Necropsy

A specific Example of applied Research Results will be through
the Collection of Data on Ingestion of Environmental Contaminants
and Pesticides.
Feral-Wild Mute Swans feed on Submerged Aquatic Vegetation,
and are therefore more prone to Ingestion of Contaminated Sediments,
making the Species’ Ideal Biological Indicators of Ecological Health.
Heavy Metals and Pesticides will accumulate in Tissues over Time.
Swan Death Necropsy

By testing Year-old Swans, Researchers get an Indicator of the Current
Status of the Ecosystem, which may be of particular interest in EPA
designated Areas of Concern, where large Multi-Year Ecological
Clean-up Projects are currently underway.

Swan Death Necropsy

Swan Death Necropsy