New Deer Stalking App - First Light

[smengal]

First Light — UK Deer Stalking Guide

Hi all,

I’ve been working on a free web app for UK deer stalkers called First Light, and thought I’d share it here to get some honest feedback from people who actually spend real time on the ground.

The idea came from wanting something simple that tells you exactly what you need before heading out — legal shooting times for your precise location, what the conditions are like, and whether it’s worth getting out of bed at 4am (or even earlier).

It’s to an extent a passion project and my way of giving something back to the deer management community. It’s also a small thank‑you to the people who’ve helped me improve as a deer stalker — especially Ian Farrington and Shadab Farooqi, who’ve both been brilliant mentors and influences.

Legal shooting times

The app calculates legal start and legal end based on your set location, shows the live countdown, and works anywhere in the UK.


Deer activity forecast


This is a bit of geeky algorithm that generates live activity score built using several environmental factors and the research that’s out there.
The weighting draws on:

• Beier & McCullough (1990) — patterns of deer movement relative to dawn/dusk
• Lomas & Byers (2013) — barometric pressure as a predictor of ungulate activity
• Ciuti et al. (2009) — temperature suppression of roe deer movement
• Knight’s original solunar theory (1936) — still widely used and supported by various behavioural observations over the decades

The model then layers in:

• moon phase
• solunar periods
• barometric pressure trend
• temperature
• wind
• cloud cover
• rut timing for all six UK species
• seasonal body condition
• time of day

Just to be upfront: it’s not a magic deer‑summoning tool. Local disturbance, forestry work, livestock, woodland density, and individual animals will always behave in ways no algorithm can fully predict.
There’s also far less UK‑specific movement research (especially for roe, fallow and muntjac) compared to the massive amount of North American whitetail literature, so the model blends what’s available with practical patterns most stalkers already recognise. It’s there to help you plan — not promise deer.

7‑day outlook

Shows dawn/dusk movement windows and conditions for the week ahead so you can plan your outings around potentially better days.

Field guide

This is the part I’m most keen to improve based on feedback.

It’s a quick reference you can use in the field, in the truck, or while brushing up for DSC1/DSC2. It covers:

• Stalking Safety — firearms handling, high‑seat safety, backstop awareness
• Deer Identification — species, sex and approximate age
• Shot Placement — anatomy, angles and vital zones
• After the Shot — blood sign, follow‑up, gralloch basics
• Carcass & Larder — hygiene, contamination risks
• Notifiable Diseases — bTB, CWD and legal reporting duties
• Rut Calendar & Behaviour — timing and behavioural cues by species
• Legal Calibres — minimum calibre and energy rules for England, Wales and Scotland

It’s not a replacement for proper training or having time on the ground with an experienced stalker — just something handy to have when you need a quick reminder.

Species guide


All six UK species with open seasons for England & Wales and Scotland, including the 2023 Scottish amendment that removed close seasons for all male deer.


Free, no login, no ads


You can use it straight away at:


First Light — UK Deer Stalking Guide


Add it to your home screen and it works like an app, including offline.

Support


There’s an optional coffee link on the site.
It’s not for profit — it just helps cover:

• domain
• hosting
• and ongoing development costs

Everything goes straight back into the app.
First Light will always be free.

Feedback welcome


I’d genuinely appreciate corrections, suggestions, criticisms — anything really — especially from those who have far more years on the hill or in the woods than I do.

 

[dryan]

Excellent and useful

 

[308rws]

Thanks, I shall give it a go.

 

[muddy42]

Thanks I'll give it a go. I find two or maybe three apps very helpful:
- the sunrise / sunset times on the basic iphone app. In my mind the ideal time to be on the ground is 30/45 mins before sunrise etc.
- Windy. shows the localised wind direction. Good, but I often find it underestimates the prevailing wind, meaning I take weak North easterly winds with a pinch of salt.
- RainToday. shows you a map of rainfall in the next hour. Im normally clutching at straws if using this.

 

[Tim.243]

First Light — UK Deer Stalking Guide

Hi all,

I’ve been working on a free web app for UK deer stalkers called First Light, and thought I’d share it here to get some honest feedback from people who actually spend real time on the ground.

The idea came from wanting something simple that tells you exactly what you need before heading out — legal shooting times for your precise location, what the conditions are like, and whether it’s worth getting out of bed at 4am (or even earlier).

It’s to an extent a passion project and my way of giving something back to the deer management community. It’s also a small thank‑you to the people who’ve helped me improve as a deer stalker — especially Ian Farrington and Shadab Farooqi, who’ve both been brilliant mentors and influences.

Legal shooting times

The app calculates legal start and legal end based on your set location, shows the live countdown, and works anywhere in the UK.


Deer activity forecast


This is a bit of geeky algorithm that generates live activity score built using several environmental factors and the research that’s out there.
The weighting draws on:

• Beier & McCullough (1990) — patterns of deer movement relative to dawn/dusk
• Lomas & Byers (2013) — barometric pressure as a predictor of ungulate activity
• Ciuti et al. (2009) — temperature suppression of roe deer movement
• Knight’s original solunar theory (1936) — still widely used and supported by various behavioural observations over the decades

The model then layers in:

• moon phase
• solunar periods
• barometric pressure trend
• temperature
• wind
• cloud cover
• rut timing for all six UK species
• seasonal body condition
• time of day

Just to be upfront: it’s not a magic deer‑summoning tool. Local disturbance, forestry work, livestock, woodland density, and individual animals will always behave in ways no algorithm can fully predict.
There’s also far less UK‑specific movement research (especially for roe, fallow and muntjac) compared to the massive amount of North American whitetail literature, so the model blends what’s available with practical patterns most stalkers already recognise. It’s there to help you plan — not promise deer.

7‑day outlook

Shows dawn/dusk movement windows and conditions for the week ahead so you can plan your outings around potentially better days.

Field guide

This is the part I’m most keen to improve based on feedback.

It’s a quick reference you can use in the field, in the truck, or while brushing up for DSC1/DSC2. It covers:

• Stalking Safety — firearms handling, high‑seat safety, backstop awareness
• Deer Identification — species, sex and approximate age
• Shot Placement — anatomy, angles and vital zones
• After the Shot — blood sign, follow‑up, gralloch basics
• Carcass & Larder — hygiene, contamination risks
• Notifiable Diseases — bTB, CWD and legal reporting duties
• Rut Calendar & Behaviour — timing and behavioural cues by species
• Legal Calibres — minimum calibre and energy rules for England, Wales and Scotland

It’s not a replacement for proper training or having time on the ground with an experienced stalker — just something handy to have when you need a quick reminder.

Species guide


All six UK species with open seasons for England & Wales and Scotland, including the 2023 Scottish amendment that removed close seasons for all male deer.


Free, no login, no ads


You can use it straight away at:


First Light — UK Deer Stalking Guide


Add it to your home screen and it works like an app, including offline.

Support


There’s an optional coffee link on the site.
It’s not for profit — it just helps cover:

• domain
• hosting
• and ongoing development costs

Everything goes straight back into the app.
First Light will always be free.

Feedback welcome


I’d genuinely appreciate corrections, suggestions, criticisms — anything really — especially from those who have far more years on the hill or in the woods than I do.

My first port of call would be the owner to see if they are working the fields that morning (conflict of day work)
Look at the wind direction
Then sunrise/set on the BBC local weather
99% of my stalking is up to last light so tonight is Sunset18:15 + 1hr

Looks very neat so well done

 

[Long drag]

Impressed, good idea like it.

 

[Jh1986]

Initial thoughts are that it's a useful little app that brings a lot of the features I use from my current go to (MyHunt). I jump on every night before, and morning of, to view sunrise/sunset, wind, moon phase etc.

All things this app also does, however I like the additional resources of the Field Guides.

One thing I would say is that, particularly for the species, I'd like the images to be more factual rather than a cartoon. We're talking about species of deer, so proper pictures would be much better.

 

[smengal]

Initial thoughts are that it's a useful little app that brings a lot of the features I use from my current go to (MyHunt). I jump on every night before, and morning of, to view sunrise/sunset, wind, moon phase etc.

All things this app also does, however I like the additional resources of the Field Guides.

One thing I would say is that, particularly for the species, I'd like the images to be more factual rather than a cartoon. We're talking about species of deer, so proper pictures would be much better.

Yes, in process of doing that for next version. Thanks.

 

[Dave5463]

Looks good @smengal thanks for sharing.

 

[VSS]

Thanks for sharing that

 

[NullMac]

Yon algorithm is nae going tae work.

It’s too simple as it is based on current conditions whereas the prediction is more of a time series analysis or LSTM RNN where the previous states will affect the forecast outcome.

It also does not allow for local ‘herd’ behaviours eg wild Scottish Sika vs more forgiving southern Sika; farm roe vs woodland roe.

I doubt there is data to train a model and the heuristics from a couple of academic papers are going to have to do a lot of work to predict what a deer thinks

But maybe the users won’t care. It’s on trend so maybe it will be popular.

Good luck

 

[VSS]

Yon algorithm is nae going tae work.

It’s too simple as it is based on current conditions whereas your prediction is more of a time series analysis or LSTM RNN where the previous states will affect the forecast outcome.

It also does not allow for local ‘herd’ behaviours eg wild Scottish Sika vs more forgiving southern Sika; farm roe vs woodland roe.

I doubt there is data to train a model and the heuristics from a couple of academic papers are going to have to do a lot of work to predict what a deer thinks

But maybe the users won’t care. It’s on trend so maybe it will be popular.

Good luck

It's fun trying, though!
Fair play to the OP for having a crack at it.
I haven't had a close look at it yet, but if it includes an option for stalkers to input data then it could presumably become more and more accurate over time?

 

[KentCountryGent]

Thanks I'll give it a go. I find two or maybe three apps very helpful:
- the sunrise / sunset times on the basic iphone app. In my mind the ideal time to be on the ground is 30/45 mins before sunrise etc.
- Windy. shows the localised wind direction. Good, but I often find it underestimates the prevailing wind, meaning I take weak North easterly winds with a pinch of salt.
- RainToday. shows you a map of rainfall in the next hour. Im normally clutching at straws if using this.

Plus one for Windy - great free app which shows you wind direction and sunset sunrise also. Zooming in shows you an OS style map making it easy to look over bits of ground.

 

[nathan22]

Sounds epic ill take a look now also use windy its very good

 

[sh1kar]

Sounds good but I guess
For lowland its Missing arable crop Rotation. Livestock movements Forestry operations

Knowing these then adding the app I can see be useful

S

 

[smengal]

Yon algorithm is nae going tae work.

It’s too simple as it is based on current conditions whereas the prediction is more of a time series analysis or LSTM RNN where the previous states will affect the forecast outcome.

It also does not allow for local ‘herd’ behaviours eg wild Scottish Sika vs more forgiving southern Sika; farm roe vs woodland roe.

I doubt there is data to train a model and the heuristics from a couple of academic papers are going to have to do a lot of work to predict what a deer thinks

But maybe the users won’t care. It’s on trend so maybe it will be popular.

Good luck

Cheers for taking the time to comment, genuinely appreciate it.

You’re absolutely right that no simple app is ever going to properly predict deer movement. To do that you’d need years of telemetry, proper time‑series data, herd‑level behaviour, local ground pressure… all the stuff nobody has for UK deer. And even if we did have it, you’d be into full ML territory with LSTMs and historic state modelling. So yes no disagreement from me at all.

The movement score in the app isn’t trying to do anything like that. It’s just a lightweight heuristic based on the bits of research that do exist and the common field patterns most of us already notice: dawn/dusk activity, pressure changes, temperature swings, moonlight, rut periods, that sort of thing. It’s meant to give you a feel for how favourable conditions look, not to guess what any given deer is going to do. Ground pressure, forestry work, farm activity and individual animals will always blow any model out the water.

And honestly, the activity bit is only a tiny part of the app. The main reason I built it was for the stuff stalkers, particularly beginners, actually need every single outing:

• legal start / legal end for your exact location
• live countdown
• 7‑day sunrise/sunset forecast
• season dates for all six species
• quick‑reference field guide (UKDTR, notifiable disease phone numbers etc)
• safety reminders, shot placement, carcass hygiene

That’s the core purpose, the movement score is more of a fun bonus tool rather than the heart of the thing.

 

[oldhamstocks]

Well done! Looks good, will have a proper play tomorrow, cheap coffee sent!

 

[smengal]

Sounds good but I guess
For lowland its Missing arable crop Rotation. Livestock movements Forestry operations

Knowing these then adding the app I can see be useful

S

Totally agree, the local factors make the main difference.

 

[smengal]

Well done! Looks good, will have a proper play tomorrow, cheap coffee sent!

Thank you sir!

 

[WalkedUp]

Great work