Winter trapping - is it worth it?

Because a lot of people put their traps away for the winter, I thought I'd take a quick look at what might be missed in the garden if I did the same thing.  Looking purely at macro-moth first sightings (and ignoring abundance altogether for the moment), I've gone back over ten years to dig out the data for those species seen here at Westcott prior to 31st March.  There are 36 of them in all but the most I've ever seen in one season is 26 (in 2011).  Their details appear in the table below:  

Macro Species	2006	2007	2008	2009	2010	2011	2012	2013	2014	2015
March Moth	23/3	6/3	7/2	6/3	24/2	16/2	24/2	4/3	16/3	24/2
Shoulder Stripe		6/3	15/3	6/3	17/3	7/3	24/2		7/3	19/3
Streamer									29/3
Red-green Carpet										20/3
Winter Moth	1/1		10/1		18/1	1/1	5/1			1/1
Double-striped Pug			20/3			29/3	30/3
Early Tooth-striped				30/3
Early Thorn		8/3	14/3			21/3	11/3		16/3
Small Brindled Beauty	12/2			19/3			1/3	5/3
Pale Brindled Beauty	18/1	31/1	22/1	25/1	18/1	13/1	24/1	3/2	17/1	11/2
Oak Beauty		7/3	6/3		13/3	10/3				21/3
Spring Usher			22/1	18/2	2/2	7/2	18/1	13/1	7/2
Dotted Border	25/3	18/2	7/2	23/2	13/3	7/2	23/2	14/2	18/2	24/2
Mottled Umber	9/1				18/1	11/1				2/1
Engrailed		10/3		22/3		12/3	8/3
Early Moth	31/1	31/1	22/1	24/2	25/1	13/1	11/1	15/2	16/2	7/2
Red Chestnut		12/3	13/3		25/3	25/3	24/3		10/3
Pine Beauty						25/3			17/3
Small Quaker	25/3	6/3	22/2	14/3	17/3	23/2	8/3		8/3	11/3
Blossom Underwing				30/3		28/3	24/3
Lead-coloured Drab	23/3	7/3	6/3		17/3	21/3	8/3		22/2	29/3
Powdered Quaker		28/3		21/3		24/3	28/3		30/3
Common Quaker	25/3	20/2	22/2	27/2	16/3	23/2	24/2		19/2	28/2
Clouded Drab	25/3	24/2	28/2	19/2	16/3	22/2	8/3		5/3	11/3
Twin-spotted Quaker		12/3	14/3	14/3	23/3	11/3	8/3		14/3	19/3
Hebrew Character	19/3	3/3	9/2	27/2	16/3	23/2	21/2	14/3	22/2	2/3
Satellite	23/3	8/3		15/2	24/2	23/2	14/2		26/2	26/3
Chestnut	9/1	20/2	22/2		17/1	25/1	9/1	7/1	26/2	25/1
Dark Chestnut	18/1	4/1		18/2				2/1	17/2	25/1
Dotted Chestnut				21/3						26/3
Pale Pinion		12/3			16/3				18/3	18/3
Grey Shoulder-knot			2/3		13/3		28/2			11/3
Early Grey		11/3	14/3	17/3		15/3	9/3		14/3	20/3
Angle Shades		28/3					29/2
Oak Nycteoline		25/3				29/3
Herald				30/3					29/3
Total to 31st March	15	23	20	21	20	26	25	9	22	22
Total to 31st Dec	297	263	253	274	283	275	266	306	307

Of the species listed, all of them usually continue flying into early April (or else come back again later in the year) apart from Small Brindled Beauty, Pale Brindled Beauty, Spring Usher & Early Moth, so if one was to resume trapping on 1st April after a winter break, around here those are the only four species liable to be missed.  Small Brindled Beauty seems to me to be quite an uncommon garden moth, but in my experience the other three are just as likely to turn up to porch lights or lit windows as they are in the trap so it might actually be possible to miss none of them at all.  For myself I'm certainly not going to give up trapping during the winter months but I can see why others do! 

The macro totals to 31st December show that there's no correlation at all between how many species are seen by 31st March and what the rest of the year might might bring.  In fact the two winters which had well below average sightings in the above table (2006 and 2013) went on to produce very good species totals by the end of the year.

Dotted Border, Westcott 24th February 2015

Early Grey & Pale Pinion, Westcott 20th March 2015

Oak Beauty, Westcott 21st March 2015

Lead-coloured Drab, Westcott 29th March 2015

I've not looked closely at micro species because those few that are caught in the first three months of the year are all hibernators apart from Diurnea fagella and Tortricodes alternella.  The latter would be the only species liable to be missed because D.fagella normally continues flying into April.

Now, because some people have also been commenting on how dire the start to this year has been, I have repeated the macro-moth exercise but looked instead at abundance.  The table below lists the total numbers of moths seen in the garden here during the first three months of each year:

Macro Species	2006	2007	2008	2009	2010	2011	2012	2013	2014	2015
March Moth	2	5	6	5	9	11	9	2	4	10
Shoulder Stripe		5	2	6	3	13	23		9	7
Streamer									1
Red-green Carpet										1
Winter Moth	2		3		2	2	3			2
Double-striped Pug			1			1	1
Early Tooth-striped				1
Early Thorn		4	2			3	5		9
Small Brindled Beauty	1			1			2	1
Pale Brindled Beauty	4	6	7	13	18	8	36	3	3	8
Oak Beauty		4	7		5	2				1
Spring Usher			2	2	4	1	8	1	1
Dotted Border	2	10	4	13	7	11	24	3	14	27
Mottled Umber	1				1	1				2
Engrailed		1		1		5	4
Early Moth	3	3	2	1	1	16	11	5	3	8
Red Chestnut		3	6		1	2	2		2
Pine Beauty						2			1
Small Quaker	2	74	24	15	23	117	390		42	14
Blossom Underwing				1		1	1
Lead-coloured Drab	2	10	1		16	1	14		4	2
Powdered Quaker		1		1		6	6		1
Common Quaker	17	222	29	104	65	291	272		229	88
Clouded Drab	4	73	43	54	95	150	178		146	74
Twin-spotted Quaker		7	2	11	12	12	36		4	3
Hebrew Character	10	50	33	77	143	121	306	1	171	133
Satellite	1	2		10	5	9	17		2	1
Chestnut	7	6	1		6	8	12	3	6	7
Dark Chestnut	2	3		2				3	1	3
Dotted Chestnut				1						1
Pale Pinion		2			2				1	3
Grey Shoulder-knot			1		3		1			3
Early Grey		5	2	2		3	11		7	4
Angle Shades		1					2
Oak Nycteoline		1				1
Herald				1					3
Total to 31st March	60	498	178	322	421	798	1374	22	664	402

In a way this goes to show how short our memories can be!  True, the start to the year hasn't been brilliant but for my garden it is only 70 or so moths below the average for the last 10 years and certainly wasn't anywhere near as dire as 2006 or 2013.