Eric Mussen, Extension emeritus (Photo by Kathy Keatley Garvey)

Back in 2010, two innovators with the UC Davis Department of Entomology (now the UC Davis Department of Entomology and Nematology) decided that "The 12 Days of Christmas" ought to be replaced with insects.  

Remember that iconic song, "The 12 Days of Christmas?" Published in 1780, it begins with "On the first day of Christmas, my true love gave to me, a partridge in a  pear tree?" Eleven more gifts follow: "2 turtle doves, 3 French hens, 4 calling birds, 5 gold rings, 6 geese-a-laying, 7 swans-a-swimming, 8 maids a'milking, 9 ladies dancing, 10 lords-a-leaping, and 11 pipers piping."

The two innovators--Extension apiculturist Eric Mussen (with the department from 1976-2014 and now emeritus) and yours truly (with the department since 2005)--decided that "5 gold rings" ought to be "five golden bees."  The duo also figured that varroa mites, and other pests of California agriculture, should be spotlighted.  Don't know what happened to the varroa mites! Hey, Eric, where did you put the varroa mites?

They penned the lyrics for the department's holiday gathering. Then Mussen, who sings with a Davis-based doo wopp group, led the department in song.

That was supposed to be the end of it. Not so. It went viral when U.S. News picked it up.

On the first day of Christmas, my true love gave to me, a psyllid in a pear tree.

On the second day of Christmas, my true love gave to me, 2 tortoises beetles and a psyllid in a pear tree

On the third day of Christmas, my true love gave to me, 3 French flies, 2 tortoise beetles and a psyllid in a pear tree

On the fourth day of Christmas, my true love gave to me, 4 calling cicadas, 3 French flies, 2 tortoise beetles and a psyllid in a pear tree

On the fifth day of Christmas, my true love gave to me 5 golden bees, 4 calling cicadas, 3 French flies, 2 tortoise beetles and a psyllid in a pear tree

On the sixth day of Christmas, my true love gave to me 6 lice a'laying, 5 golden bees, 4 calling cicadas, 3 French flies, 2 tortoise beetles and a psyllid in a pear tree

On the seventh day of Christmas, my true love gave to me 7 boatmen swimming, 6 lice a'laying, 5 golden bees, 4 calling cicadas, 3 French flies, 2 tortoise beetles and a psyllid in a pear tree

On the eighth day of Christmas, my true love gave to me 8 ants a'milking aphids, 7 boatmen swimming, 6 lice a'laying, 5 golden bees, 4 calling cicadas, 3 French flies, 2 tortoise beetles and a psyllid in a pear tree

On the ninth day of Christmas, my true love gave to me 9 mayflies dancing, 8 ants a'milking aphids, 7 boatmen swimming, 6 lice a'laying, 5 golden bees, 4 calling cicadas, 3 French flies, 2 tortoise beetles and a psyllid in a pear tree

On the tenth day of Christmas, my true love gave to me 10 locusts leaping, 9 mayflies dancing,  8 ants a'milking aphids, 7 boatmen swimming, 6 lice a'laying, 5 golden bees, 4 calling cicadas, 3 French flies, 2 tortoise beetles and a psyllid in a pear tree

On the 11th day of Christmas, my true love gave to me 11 queen bees piping, 10 locusts leaping, 9 mayflies dancing, 8 ants a'milking aphids, 7 boatmen swimming, 6 lice a'laying, 5 golden bees, 4 calling cicadas, 3 French flies, 2 tortoise beetles and a psyllid in a pear tree

On the 12th day of Christmas, my true love gave to me 12 deathwatch beetles drumming, 11 queen bees piping, 10 locusts leaping, 9 mayflies dancing, 8 ants a'milking aphids, 7 boatmen swimming, 6 lice a'laying, 5 golden bees, 4 calling cicadas, 3 French flies, 2 tortoise beetles and a psyllid in a pear tree

"On the 13th day of Christmas, Californians woke to see:

 13 Kaphra beetles, 
12 Diaprepes weevils, 
11 citrus psyllids,

10 Tropilaelaps clareae, 
9 melon fruit flies, 8 Aedes aegypti, 7 ash tree borers, 6 
six spotted-wing Drosophila, 5 
five gypsy moths, 4 Japanese beetles, 3 imported fire ants, 2 brown apple moths, and a medfly in a pear tree."

Mussen, although retired in 2014, keeps bee-sy.  A co-founder of  Western Apicultural Society (WAS), he completed his sixth term as president in 2017.  WAS, which serves the educational needs of beekeepers from 13 states, plus parts of Canada, was founded in 1977-78 for “the benefit and enjoyment of all beekeepers in western North America."

Mussen also continues to answer bee questions from his office in Briggs Hall and recently updated the "13 Bugs of Christmas" lyrics with some more agricultural pests:

On the first day of Christmas, my true love gave to me, a psyllid in a pear tree.
One the second day of Christmas, my true love gave to me, two peach fruit flies
On the third day of Christmas, my true love gave to me, three false codling moths
On the fourth day of Christmas, my true love gave to me, four peach fruit flies
On the fifth day of Christmas, my true love gave to me, five gypsy moths
On the sixth day of Christmas, my true love gave to me, six white striped fruit flies
On the seventh day of Christmas, my true love gave to me, seven imported fire ants
On the eighth day of Christmas, my true love gave to me, eight longhorn beetles
On the ninth day of Christmas, my true love gave to me, nine melon fruit flies
On the 10th day of Christmas, my true love gave to me, ten brown apple moths
On the 11th  day of Christmas, my true love gave to me, eleven citrus psyllids
On the 12th day of Christmas, my true love gave to me, twelve guava fruit flies.
On the 13th day of Christmas, my true love gave to me, thirteen Japanese beetles

You're welcome.