Finnish Focus On...Taiga And Tundra Bean Geese

Have been meaning to write a post on Tundra and Taiga Bean Goose identification for a while now.

Wildfowl are my guilty pleasure. I've always enjoyed looking for them. The escape issue turns a lot of people off them. Grey geese can turn people off further still.

Since moving to Finland, being able to spend long hours in the field watching both types of Bean Goose has been a joy, especially considering how rare they are in Ireland. 

Tundra Bean Geese are the far commoner species to occur here, making them the easier to photograph and so a good place to start.

Tundra Bean Goose



Tundra Bean Goose - careful assessment of structure is most important when identifying bean geese. Whilst there are size differences between the smaller Tundra and larger Taiga, this plays out most obviously in their structure and shape. Both species, rear on, can be extremely difficult to pick apart without the structural clues visible.




The head and bill structure are crucial in Bean Goose identification. This bird above is typical in every respect. Note the isoceles triangle shaped bill, deep based, equally distributed between upper and lower mandible. The head is done shaped, with an obvious forehead, kinked where it meets the bill.


Tundra Bean Geese - a variety of head and bill shapes. 






A range of Tundra Bean Geese head and bill structures.





Tundra Bean Goose - a typical dinky, cute looking bird. 




Tundra Bean Goose - birds with increased orange on the bill can make it harder to discern the typical grimace look, though it is often still there. 


Tundra Bean Goose - not infrequently you come across birds like this. Long bodied, wedge-headed, no obvious forehead kink, smooth chinned and longer billed than average. 
These are wannabe Taiga. 
The neck is, however, short and thick.
Careful study of the bill reveals a telltale structure. 





Tundra Bean Goose - at the other end of the scale, dinky birds approaching Pink-Footed Goose in appearance.


Tundra Bean Geese - again a range of structures and bill patterns.



Tundra Bean Goose - birds stretching the neck can cause momentary alarm, especially when very orange billed.



Looking closer reveals a typical Tundra bill structure, despite the extensive orange. 


At times, both species of Bean Goose can display varying levels of a white blaze at the bill base. In my experience, Taiga tends to display this more frequently, but there is overlap.


Tundra Bean Goose - a large bodied bird, but otherwise fairly typical.


Tundra Bean Goose - swimming birds can be exceptionally difficult, changing their entire posture on the water. Here the head and bill are typically Tundra.


Tundra Bean Goose - a long billed bird, head on with a stretched neck can relay a false impression of elegance.


Tundra Bean Goose - a classic individual. Dinky, dome, almost block headed, short deep bill with classic ring pattern, obvious chin, short and thick neck.


Tundra Bean Geese - mud covered birds can also take time to ID. Again, assessment of the sum of features will usually settle things.


Tundra Bean Goose - an extreme bird in terms of bill colour, but otherwise a fairly obvious Tundra. I have seen birds which lack any black on the bill.


Tundra Bean Geese - a range of bill and head shapes/ patterns.


Taiga Bean Goose

Taiga Bean Goose is a more swan-like, elegant affair, with a long, slim neck and wedge shaped, swan shaped head. The bill is generally long, and shaped like a right angled triangle. 

The facial expression of Taiga Bean Goose often feels more sculpted, with strong cheek bones and jaw-line, giving them a distinct look.

The grimace effect on the bill is less pronounced or even seemingly absent on some individuals. The bill often feels "snooty", long, tapered and often slightly decurved towards the tip.


Taiga Bean Geese - the head shape of Taiga Bean Goose, whilst often longer and more wedge shaped than Tundra, is often quite angular too, with distinct changes in slope from nape, to crown, to forehead. Tundra so often feels smoother, a more natural rounded skull shape.




Taiga Bean Geese - even when relatively short billed fo Taiga (second from the left) the head shape remains distinct. Note the angle from nape to crown. 





Taiga Bean Goose - Truly classic in all respects. Big swan-like body and long neck. Wedge shaped head, long bill with narrow base to lower mandible, smooth transitions from both forehead and chin to the bill. Eye located up and close to the contour of the head.




Taiga Bean Goose - sometimes they are simply ridiculous looking. This one is extreme in terms of almost complete orange colour on the bill. The lower mandible is barely perceptible, the bill long and right angled triangle in shape.
The neck, fully stretched is incredibly long and slim, the body large, long and swan-like. They don't come easier than this.





Taiga Bean Goose - another typical bird in terms of head and bill structure. Increased levels of orange on the bill seems to be more regular in Taiga than Tundra in my opinion.



Taiga Bean Geese - In my experience Taiga seem more faithful to family groups than Tundra, which seem to wander more freely within flocks, but this may be due to lower numbers of Taiga naturally sticking together when surrounded by their smaller cousins.

The left hand bird here is slightly more Tundra-like in terms of rounded head shape and slightly thicker neck.




Comparisons


Taiga Bean Goose variation


Tundra Bean Goose variation



Taiga vs. Tundra


Taiga vs. Tundra


Taiga vs. Tundra

What to remember

  • Bill shape - is it more isoceles triangle shaped, with a broad base to lower mandible? (Tundra) Or is it long and right angled, with a narrow base to the lower mandible? (Taiga)
  • Neck length and thickness - Short, thick and sturdy? (Tundra) or Long, slim and elegant (Taiga)
  • Head shape - small, domed/rounded with an obvious kink meeting the bill? (Tundra) or long, wedge shaped, with smooth transition into the bill? (Taiga)
  • Body shape - compact and cute/dinky? (Tundra) or large, long and swan-like? (Taiga)
  • Assess and weigh all features, keeping overlap in mind. 
  • It's OK to let birds go - some distant or difficult birds may cause you trouble. Sometimes you just have to leave them in the either/or pile.
  • It's OK to make mistakes - when you start watching Bean geese you will make mistakes. It's nothing to be afraid of. Keep watching, keep working and you will be able to assign them correctly with greater and greater precision. 

Comments

  1. Fantastic. Heavily involved with monitoring the Slamannan Plateau taiga bean geese. This is surely THE tundra v. taiga i.d. article to end all such debates!!

    ReplyDelete
  2. Thank you for a brilliant article on the separation of Taiga and Tundra Bean geese. I can now go out into the field with a little more confidence in separating these two.

    ReplyDelete

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