I just wanted to take a look in to the real effects of the proposed boundary changes. Using data that I've visualised up at Boundari.es to represent the boundary changes I'm assessing not only which parties lose out in terms of seats, but also in terms of notional vote shares. Where have parties taken a hit (or been handed a life line) while not necessarily gaining or losing extra seats? Which areas seem to have confusing decisions made regarding constituency area?
It has to be stressed, this data is notional and so is a reflection of how it is likely (but not guaranteed) that constituencies would look in 2010 if the boundaries had been as they're proposed now back at that election. We know that in terms of opinion polls the Lib Dems are polling differently (lower in general, though much less lower in seats they're battling the Tories), and that Labour are doing slightly better than 2010 while the Tories are about the same.
I will be editing this post as and when I get time to do more analysis.
Cornwall loses about half a constituency through the changes, which may be a source of concern to the Cornish who, at least in the West, see themselves as very separate from the rest of England, especially Devon. In terms of seats Cornwall notionally gains a Lib Dem seat from the Tories in the process.
Cornwall remains an extremely marginal county, with differences between the Tories and Lib Dems in the area continuing to reside on a knife edge. If things have improved for the Tories it is only be a percentage point here or there and the electoral landscape for the constituencies will remain similar to that of 2010.
The major change is the loss of what was Truro and Falmouth in to the new Truro and St Austell and Bodmin and Newquay constituencies. What small majority the Tories had in either area is eaten up by the more Liberal tendencies of those in Mid to East Cornwall. On the flip side Cornwall North, just getting out of being a marginal constituency, is split up in such a way that a new super marginal Bodmin and Newquay is made, with the majority staying put in the new Devon and Cornwall constituency, Bude and Bideford. The Lib Dems sit with notional majorities of just 0.3%, 2.5%, 2.7% in 3 of their 3 and a half Cornish constituencies.
This means that while the Lib Dems may be happy with the outcome in Cornwall, it also requires a big fight from them in 2015. How many of those Lib Dem votes will remain, and how many were Labour tactical votes? Will more Labour voters go tactical to help the Lib Dems steal a marginal Falmouth and Camborne from the Tories? More importantly, will a potential resurgence in the Labour vote hurt the Lib Dems or Tories more in the county? Should the Labour votes rise at the expense of the Tories then it's feasible that the Lib Dems could, as in 2005, claim the whole of Cornwall...but on the flip side a deserting of the Lib Dems could see a sweeping move to net the Tories an additional 3 seats.
The electorate numbers look good compared to the ideal of around 76600, with only St Ives really breaking away from the average significantly. I can't initially see any reason that this should be rectified, with local areas quite well partitioned and the scope for future population increases in the mid to east of Cornwall rather than the far west of St Ives.
All in all, for Cornwall, the Lib Dems should look happiest in as exciting an electoral landscape as their usually is in the area. They do better where they're fighting marginals historically, and some sensible political moves by Labour supporters combined with natural flow back from the Tories to Labour could result in gains for the party. However similarly the Tories have to see this county as an opportunity, and as the party that tends to have more money to throw at marginals they could really hurt the Lib Dems if successful. The question is if they would be able to in a post-coalition landscape in a clearly more liberal and "locally-thinking" area. The prospects for Labour remain poor.
Devon's 12 constituencies become 11 and a half, losing half a constituency to the Bude and Bideford merger with what was Cornwall North in 2010, and with the redrawing of boundaries the seat winners bring about a single Tory seat lost as Devon South West effectively gets squeezed down and merged in to Plymouth Sutton.
Devon remains fairly close to the ideal number of electors, with Plymouth Devonport alone standing out as a slightly larger than average population. Marginality does change, however. While most areas stay the same, the loss of half a constituency helps to make constituencies held by the Tories more likely to be quite safe. Devon West and Torridge was almost marginal at over 5%, but thanks to being split with Cornwall the resulting Tavistock and Plympton has a notional majority of over 20%.
The old Devon South West very safe seat (over 30% majority) may be gone, but as a consolation for the Tories the marginal Plymouth Sutton and Devonport is merged in to the safe Plymouth Sutton with a notional majority of 20.1%. Newton Abbot moves to slight marginal away from marginal status, while Central Devon gets a little less safe but still on the very edges of a significant swing (now 13.5% down from over 17%).
Devon is a county with a mixed bag through these changes. On one hand there are several constituencies that are literally untouched, or that are changed very little, yet on the other where significant changes have happened they have tended to significantly solidify a party's support base. Labour will be happy that in the seats that they control, Plymouth Devonport and Exeter, they are no worse off (a little better off in Plymouth), and the Lib Dems are untouched in the county aside from that Cornwall and Devon constituency creeping in from North Cornwall. The Tories will no doubt be disappointed to lose an MP, but they have at least not lost it to another party and have shored up support elsewhere.
Somerset has actually gained a constituency, up to almost 10 from 9. I say almost 10 as it has taken a very small part of what I would personally consider to be outer Bristol. In doing so the Tories are gaining a seat out of nowhere for the county.
There are some significant boundary movements, but little changes on marginality. Tory majorities in the region stay the same while the new constituency, Kingswood & Keynsham, makes a slightly safe seat at around 10% majority.
The Lib Dems, while shifting their area of representation out of the Wells area and more to the area around Bath, can be happy that they slightly increase their strength of standing. Their marginal seats are still marginal, but a percentage or two less so, and their only real loss in majority is Bath, where they can afford to lose the 5% to a notional 20.4% majority.
Electorate numbers are more interesting. Somerset is a county that, through the addition of the new constituency perhaps, has a lower number of electors than the threshold in large areas. Yet at the same time Weston-Super-Mare and North West Somerset have a couple of extra thousand. This is arguably the right way around, with more likelihood of population moving in to the larger constituencies and thus allowing for a rebalancing that avoids drastic boundary changes in the future.
Could the extra 2-3000 extra people over the threshold in those two constituencies be better represented in other constituencies, or is it (as is more likely) that being able to split just that amount of people out of these larger constituencies would provide too complicated when trying to adhere as much as possible to previous separations of populations such as at local council level? I tend to think it's the latter in most cases, your mileage may vary.
Somerset really doesn't feel like it is affected by these changes, indeed it may be a benefactor through an extra MP for the area in a scheme designed to reduce MP numbers! Marginality stays the same, and while there will be changes to make to local campaigns the status quo is mostly upheld.
Dorset sees a slight reduction in representation, losing about half a constituency to share with Wiltshire to the north. In a process that sees Dorset North cut up to help enlarge Christchurch, Dorset Mid and Poole North, and Wiltshire South West the net effect is the Lib Dems losing their seat in the area, though no-one picks it up since it disappears.
The already super marginal Lib Dem seat shows that the Lib Dems really don't have a chance in the area under the new desired populations for each constituency, their support is simply too low. The only hope for the Lib Dems in the area is a slightly reshaped Bournemouth West that is held by a 6.4% majority. Labour on the other hand are as shut out of the county as ever, with Tory majorities being largely untouched aside from that part of Bournemouth, and the new constituency of Blandford & Wimborne being an almost straight Tory vs Lib Dem fight, unlikely to be lost by the blues.
When it comes to population there is a question that hangs over just why both Bournemouth seats need to be so overpopulated (over 80,000 electors in each constituency) when Christchurch and South Dorset are both significantly under the ideal threshold. In my mind it is worth asking why areas of the Bournemouth seats couldn't be pushed out to their neighbours, with a view to increasing the size of Dorset South to the West and Christchurch to the East.
Dorset is, if anything, a score draw for all parties. The changes are significant in the center of the county, but don't serve to make many changes. Even the Lib Dem loss is arguably a Tory loss, as the margins were such that it would surely be one of the main targets in the country at the next election.
Gloucestershire and Bristol Area:
I have a bit of a personal interest in this area, it's my current "hometown" as it were! Bristol is what I would define as the 6 constituencies around the city center, including Kingswood and Filton & Bradley Stoke. This distinction gets blurred under the new boundaries as Thornbury and Yate gets split in half, encroaching on the old Kingswood constituency, and Filton & Bradley Stoke join with Thornbury to become Filton & Thornbury.
Further north, in to Gloucestershire actual, the remaining 7 constituencies in this area are unchanged aside from the already mentioned breaking up of Thornbury and Yate, and a small boundary shift between The Forest of Dean and Gloucester.
The overall effect of all this is that Kingwood and Keynsham is now more of a Somerset constituency than before (see above), essentially being lost from the area, leaving 12 constituencies compared to 13 before. This is a net change of one Lib Dem seat to a Conservative one, however.
I have my own concern in the area, it seems ridiculous that Filton has been extended to join with Thornbury, and in doing so created the largest constituency in the area in population numbers. This is an area which has very active housing development next to the Filton Airfield that could bring hundreds, if not thousands, more people to the area. The North of Bristol is being constantly redeveloped and the boundary commission seem to be ignoring this when choosing where to pitch their numbers.
Is it right that the Filton area keeps getting cut up and redistributed 5 years because a little forethought can't be put in here? This is aside from the fact it makes no sense to put what is an edge of the city urban area in the same catchment as a countryside town.
Bristol North West and Bristol West both have population numbers under the threshold from this review, in areas where people are certainly not going to be moving in at vast numbers. Bristol West is a mixed constituency, with a large student population as well as inner city residents, while Bristol North West has it's own mix of both poor and affluent residents as it spreads out to the west.
To my mind, moving Filton and Frenchay and Stoke Park wards in to the Bristol North West constituency, while moving Avonmouth (further from the city center than Filton, and partly crossing the M5) in to the Thornbury "outer Bristol" constituency would both make more sense from the point of view of the MP representing people with similar issues, and would have a net effect of making "Thornbury and Filton" or whatever it would be called near to the ideal threshold, while Bristol North West would grow to be about 2000 people over the ideal.
This alone would be acceptable, given the population growth to the north of Bristol as I said before, but it could also be even further balanced by swapping Stoke Bishop and Bishopston wards between Bristol North West and Bristol West.
Elsewhere in the area Bristol South seems a little over subscribed, but has little easy way to balance this with the Kingswood and Keynsham constituency next door. The Forest of Dean could easily do with a larger area, but with wards so large in the mainly rural outskirts to the constituency there is little prospect to do this without significantly (and arguably needlessly) messing with the already established constituencies that remain unchanged from 2010.
Gloucestershire itself has very little to show from the review, barely any boundary changes and thus no real change of marginality. Bristol's outskirts, however, get a thorough overhaul. Do the Lib Dems need to lose their seat in this way? It's another of those situations that is more complex than it seems, as a strong Tory and Lib Dem seat is turned in to a weak tory seat and better than halves the previous Filton area majority to 6.2% making both very attainable to the Lib Dems. Labour suffer slightly on Bristol East, but remain in a good position in a three way marginal (of which Bristol has two, lucky for us!)
Herefordshire, Shropshire and Worcestershire:
Herefordshire somewhat loses it's identity through the changes. A simple county of two constituencies only has one within it's borders after the provisional changes. In technical terms though it now becomes three constituencies, two shared with neighbouring Worcestershire and Shropshire. The overall effect of this is a single seat lost across all three counties.
While the Conservative constituencies get shunted around quite a lot, the loser in this area is Labour who's Telford constituency is the one that effectively disappears. This isn't much of a surprise given how small a majority Telford was held on, and concentrated in to such a small geographical area. This won't lead to anything more interesting, however, majorities at a safe level and beyond even any reasonable tactical voting thresholds the worst that can be said from a Conservative point of view is that a few very safe seats have turned to merely being safe.
Electorate sizes are fairly well balanced given the largely rural nature of the counties, and aside from the loss of a Labour constituency there is little interesting that is happening through these changes; there are simply too many Tory supporters in the area to make the changes significant, despite some fairly drastic redrawing of boundaries.